Monday, May 23, 2011

Going Dark

I will not be posting any more this month or during the first week in June. I have a pressing, self-imposed obligation demanding my attention.

On Memorial Day, please remember to think of our troops. Consider doing something nice for one or more of them to show your appreciation.

tsj

Saturday, May 21, 2011

Automating Wrongful Convictions: Overshooting The Mark

In the previous post of this indefinitely long series, I explained how Optotraffic's Automated Speed Enforcement system can report a car to be traveling 52 miles per hour when in fact the car is actually traveling at 35 miles per hour. This particular error is created when the lasers are not parallel to the road and strike the near side of the car rather than the centerline.

In this post, I discuss a similar error, this one caused when the lasers nearly overshoot (rather than nearly undershoot) the car. The potential error in this case is even greater than the previous case.

The lasers are more likely to overshoot the vehicle when the vehicle is passing the laser system in the nearest lane, as shown below.


The beams tend to overshoot the vehicle when some combination of the following conditions exist:
1. The laser beams are not properly aligned.
2. The cart is located too near the road.
3. The vehicle is not on the centerline of the road.
4. The cart is tilted away from the road.
5. The wind bends the 32' tower away from the road.
6. The lane is narrower than usual.
Any behavior that causes the laser beams to strike the vehicle beyond the centerline increases the chance that the system will overpredict the vehicle speed due to an overshoot.

The other factor that contributes to speed errors due to overshoot (or undershoot) are beams not perpendicular to the road. I describe these beams as being yawed. The beams can be yawed when:
1. The laser beams are not properly aligned.
2. The laser platform is yawed relative to the 32' tower.
3. The 32' tower is twisted due to wind or cable tension.
4. The cart is not parked parallel to the road.
In this example, the cart is so close to the road that the beams hit the road 2 feet beyond the lane centerline. The pickup is traveling 8 inches from the lane centerline. The beams are yawed 10 degrees such that the first beam to strike the vehicle overshoots more than the second.

Speaking of the first beam, here's where it strikes the pickup.


In this example, the beams are 29.25 inches apart. The truck, however will travel less than 29.25 inches before the second beam hits the truck, because the second beam will strike the truck closer to its front end, as shown below.


Instead of first contacting the upper portion of the fender, as did the first beam, the second beam first contacts the outer edge of the bumper.  The distance the truck traveled between first and second beams was foreshortened by the distance between the intial contact points of the two beams. To show that distance, I dropped a vertical line from each of the contact points, backed the pickup up, and measured the distance between the two vertical lines.  Here you go.


Having learned from my previous post, I increased the font size of the dimension. There is no need to enlarge the image to see that the beam distance was foreshortened by 14.69". (Feel free to click and enlarge if you wish.)

I think that might result in a substantial error. Let's check.

The actual distance traveled between beam contacts will be 29.25" - 14.69" = 14.56".  The system will assume the distance traveled was 29.25 inches. The speed calculation will be off by a factor of  29.25/14.56 = 2.

Holy Frijole!

Assuming an upstanding citizen passed beneath the Space Sigma Optotraffic DLS-10S Automated Speed Enforcement system under the conditions just described, and assuming that upstanding citizen was traveling at 35 miles per hour, that upstanding citizen would receive a speeding ticket in the mail for traveling 70 miles per hour.

TUC (the upstanding citizen) would be rightfully peeved, knowing that he or she never traveled anywhere near 70 miles per hour down that stretch of road. TUC might decide to fight the ticket rather than subserviently pay the $40 ticket by mail. TUC would decide to take a half day off work (assuming he or she was still employed in this economy) and sit through hours in a courtroom until the State was ready to hear his or her case. TUC might explain that he/she lives in the area, knows exactly where the piece of crap sophisticated laser system is parked, and explains that he/she would never travel 70 mph on that road even if the system wasn't there.

The representative from Optotraffic would explain to the judge their sophisticated system uses lasers that are calibrated against GPS beam pulses every single day. The judge would bang his gavel against that really cool gavel banging thing, and justice would be administered. TUC would be charged $40 for the ticket, and $44 for bothering the court.

Meanwhile, the Sigma Space Optotraffic web site will continue to offer the following quotes from President / CEO Marcos Sirota:
“Optotraffic is in the business of helping to protect public safety. Our company’s public trust and reputation are built entirely on the precision and highest degree of accuracy of our systems. We are proud that our calibration and testing are trusted and have been verified by the many Maryland municipalities that use our systems."
“Certainly, no one likes getting a speeding ticket, let alone paying a fine. And speed enforcement systems clearly do provide revenue for municipalities, revenue which by law is invested in further protecting public safety.”

ADDENDUM
For those of you who believe I must be three-dimensionally delusional when I suggest that the system may miscalculate the speed by a factor of 2, consider this article from The Washington Examiner, excerpted below.
A Maryland speed camera contractor is investigating whether its cameras have been miscalculating the speeds of large vehicles in Prince George’s County.

Lanham-based Optotraffic is analyzing a dozen citations that recorded buses and trucks exceeding the speed limit by more than 25 mph, Optotraffic CEO Marcos Sirota told The Washington Examiner.

Sirota began investigating citations when a camera on Rhode Island Avenue and 38th Street in Brentwood caught bus driver Kathleen LaFortune driving 58 mph in a 25 mph zone.

“I was absolutely devastated when I saw the ticket,” said LaFortune, who told The Examiner she drives past the camera 11 times daily on her bus route — which she has driven for the last year. “I have never broken the speed limit. There is just no way this is possible.”

Sirota said he is determining whether LaFortune’s ticket is valid. “Nothing immediately indicates there’s been a mistake,” he said. “We are identifying instances with some commonality so we can compare.” ...

Another driver is contesting a ticket that says his bus barrelled 78 mph through a 35 mph zone on Bladensburg Road — just one-half mile from where LaFortune was ticketed.

“These tickets are just exploding,” said Rick Hilmer, fleet management administrator. Hilmer said his office — which collects county bus drivers’ tickets—is averaging 30 citations a day.

Susan Hubbard, spokeswoman for Prince George’s Department of Public Works and Transportation, said she could not imagine a bus nearing 60 mph where [the unfortunate] LaFortune was ticketed. But [the unfortunate] LaFortune could not contest her July 28 ticket.

She [the unfortunate LaFortunate] says she was not notified of the violation until Aug. 26, seven days past the deadline for requesting a court date. Fleet management did not receive the ticket from Brentwood officials until Aug. 16, Hilmer said.

State law requires camera operators to mail citations within two weeks of the violation. Brentwood Police Chief David Risik did not return The Examiner’s calls to confirm the ticket was mailed within the legal time frame.

[The unfortunate] LaFortune’s employer, Veolia Transportation, received the ticket Aug. 20, Hubbard said, and LaFortune said another six days passed before Veolia notified her of the violation.

Veolia then suspended [the exceptionally unfortunate] LaFortune on Aug. 27 without pay, enrolled her in a three-day “refresher” training course and warned of termination if she gets another ticket, according to an internal notice from the company’s assistant general manager.
So Optotraffic strikes again, this time getting upstanding citizen Kathleen LaFortune suspended without pay. Let's see what President/CEO Markos Sirota has to say about that.
“The commercial interests of Optotraffic are totally aligned with delivering the best, most accurate, reliable laser sensing instruments to municipalities so that speeding accidents and injuries to people can be avoided.”

“For both the municipalities and for this respected company, our collective commitment to public safety is unyielding and will never be compromised for any reason."

Tuesday, May 17, 2011

The Impending Execution of Jason Williams

Jason Oric Williams sits on Alabama's death row awaiting his execution two days hence. There is no doubt that he is factually guilty of the crimes for which he is to die. I present the following summary from the decision in Jason Oric Williams v. State of Alabama. I have removed the legal references and introduced paragraph breaks to improve the readability.
The state's evidence shows that the defendant [Jason Oric Williams] had been living in the home of Gerald and Clair Paravicini in Irvington, for approximately two weeks before February 15, 1992, the date the crimes were committed. Before that, he had lived with his former wife, Sandra Ellzey, but she had forced him to move.

The Paravicinis, whom the appellant had known for several years, had allowed the appellant to move into their home because he had no place to live. Jeffery Carr, the minor son of Mrs. Paravicini, also lived in the home.

The appellant spent the evening of February 14 and the early morning hours of February 15, 1992, drinking alcohol and taking drugs. Around 6:00 a.m. on February 15, he arrived at the Paravicini home and was admitted by Jeffery Carr after knocking on a window. He called Ellzey on a portable telephone and while they were arguing, obtained Mr. Paravicini's.22 caliber automatic rifle and some hollow-point bullets from a bedroom. He then shot Jeffery Carr in the face and, as Mr. Paravicini came to Jeffery's aid, he shot Mr. Paravicini in the chest and neck.

Jeffery ran out of the house to seek help, and Mr. Paravicini ran into the street, where he died. The appellant demanded the keys to the Paravicinis' automobile from Mrs. Paravicini and when she did not produce them, he struck her in the face with the rifle, breaking her jaw and two teeth, and he threatened to kill her. He took her purse, which contained her checkbook, credit cards, and $530 cash, and ran to the road where he attempted to commandeer a passing truck driven by Buford Billedeaua. Billedeaua stopped his truck, but then took the keys and fled into the nearby woods as the appellant fired two shots at him.

The appellant then went to the nearby home of Linda and Fred Barber. The Barbers had two sons, Bryan and Brad, who lived with them and who were present in the home at the time. When Mrs. Barber opened the door, the appellant shot her, without warning, in the face and head, killing her instantly. He then shot Mr. Barber, who was sitting in the kitchen drinking coffee, twice in the head, killing him instantly. He then shot Bryan, who was asleep in his bed, twice in the head, killing him. Brad locked himself in a bedroom, but the appellant kicked the door in and while he and Brad were struggling over the rifle, Brad was shot in the left hand. Brad broke free and fled while the appellant continued to fire at him.

The appellant took the Barbers' vehicle, a Ford Aerostar van, along with Mr. Barber's wallet, which contained approximately $50, and Mrs. Barber's purse. He was apprehended the following day in Mississippi after he telephoned Ellzey. When he was apprehended, he was in possession of the Barbers' vehicle, in which were found .22 caliber bullets. After being properly advised of his rights pursuant to Miranda v. Arizona, 384 U.S. 436, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966), he was questioned about Mr. Paravicini's rifle, and he stated that he threw the rifle off a bridge into the water as he entered Mississippi. The rifle was never recovered.

The appellant presented the defense of insanity, he alleged, caused by severe drug abuse coupled with a preexisting mental disorder. ... The appellant testified in his defense that he did not remember anything about the incident from the time he telephoned Ellzey from the Paravicini home until he realized that he was in Mississippi in a strange vehicle with a rifle and with blood on his body. However, on cross-examination, he claimed that he was hallucinating at the time of the shootings: he thought he was being attacked by a "large apparition." In addition to presenting four witnesses who testified that the appellant had been drinking alcohol and taking drugs on the night before the shootings, he testified that he had been drinking alcohol and taking drugs during the hours preceding the shootings.
Given the certainty of William's factual guilt, I stand mute with respect to his execution.

Monday, May 16, 2011

Automating Wrongful Convictions: Optotraffic System Pwned

From the Urban Dictionary, we learn that "pwned" is (or may be) a corruption of the word "owned." According to one story, the word originated in an online game called Warcraft, in which a designer misspelled "owned." When the computer beat a player, it was supposed to tell the player he "has been owned."  Instead it told him he "has been pwned."

Basically "to pwn" someone is to dominate them, to beat them.

I have written about the problems with the Optotraffic system in three previous posts, here, here, and here. Read them if you dare. The basic problem is that the system assigns traffic tickets to people who are not speeding. Optotraffic says that's not possible, that their system uses lasers that are calibrated daily against GPS signals. The wronged citizenry claims that the supporting photos prove they were not speeding. The State, who has a stunningly large financial interest in the system being correct, sides with Optotraffic and legislates a legal system designed to hide exculpatory evidence and to keep the masses paying while offering only minimal resistance.

In this post, I will show step-by-step how the laser system can go wonkers. In this post, I intend to pwn Optotraffic's DLS-10S Automated Speed Enforcement system.

The Plan

My plan, devised and put into effect last Friday, was to generate a three-dimensional computer model of the laser monitoring system, then laser-blast three-dimensional computer models of pickup trucks as they raced through the beams in digital space. I would be able to tweek the laser platform in controlled fashion, and thereby understand what sort of situations could cause the system to erroneously decide a vehicle is speeding.

For my three-dimensional modelling program, I used Google's SketchUp.  I'm wary of Google because they are becoming too powerful, and power corrupts. But darn them if they don't keep making incredible products and giving them away for free, at least in a financial sense. I use the Google search engine because Bing is still not competitive. I use Google Scholar for finding court cases, because Westlaw and Lexis/Nexis want a billion dollars to use their services. I use Blogger because it's free and because Google gives preference to Blogger posts in their search engine.

I use SketchUp as my three-dimensional modelling tool not just because it's free. It is also brilliantly designed. Absolutely brilliantly designed. Without SketchUp, I could not possibly have implemented my plan.

Also, the name SketchUp is pretty clever.

The DLS-10S Model

I needed a model of Optotraffic's DLS-10S Automated Speed Enforcement system. I built my own (simplified) model based on information I obtained from an Optotraffic 2-view drawing. The drawing was a bit cheesy, and certainly unworthy of a big time government contractor such as Sigma Space Systems. Nonetheless, it was sufficient for my purposes.

I present my simplified drawing below.


Taa Daa!

Okay. I know it's not very impressive. All I really needed was that orange (umber?) laser platform at the top. I'm going to shoot lasers from it. The rest is there for reference.

The important point about the laser platform is that it is way, way, up there. It's 32 feet tall when fully extended, according to the fine folks at Optotraffic. It sits on top of a spindly telescopic pole, and that's where it gets into trouble.

Even if you mount the world's best laser system on top of a bending, twisty, rickety pole, the end package isn't worth spit in a bottle. The weak link is definitely not the laser unit. Calibrate that until the photons come home if you wish, but it won't prove your system works. The weak link is everything else about your system, particularly the bendy, twisty, telescoping, ridiculous pole.

To give a better feel for the pole, I had Sang morph himself and stand on his own head, five times.

Perhaps now you get a better feel for how tumescent that pole might be. It's nowhere near as rigid as Optotraffic would have you believe.

Sang, by the way, is the Reference Person that comes with SketchUp 7, the version I used. If you search for information on Sang, you learn from SketchUp that:
Sang is a member of the SketchUp development team. He enjoys rock climbing, pho and long walks on the beach.
But I digress.

The Pickup Truck Model

I decided to use a pickup as the vehicle in my digital recreation. Will Foreman is an ace eight-times over for the tickets on his company pickups, and that may have influenced my decision. SketchUp allows users to post their 3-D models so others can use them, and I had many to choose from. I choose an extended cab pickup modeled by Sarge 726. I know nothing about Sarge 726 other than he makes detailed and beautiful SketchUp models of vehicles. I thank him for his effort and humbly present his model below.

Sang examines Sarge's pickup with an admiring eye.

General Arrangement

I constructed a road, put some grass around it, put some frikin' laser beams on the frikin' laser platform, put Sarge's truck on the road, and here's what I got.


Now we're getting somewhere. Sang was busy elsewhere and won't be joining us again this post.

It's extremely important that the distance between the beams on the road is the same as the distance between the beams at the laser unit. To satisfy myself that I had constructed beams that were parallel, I measure them at both the laser platform and on the road. I show my measurements at the platform first.



Previously, by back-calculating from an Optotraffic daily calibration plot, I estimated the beam distance at 30 inches. Now, by scaling (best I could) from their cheesy 2-view, I estimate the beam distance at 29.25 inches. I could still be off by a half foot or so, but I think it's close. If the beams are closer, then the error I calculate in this post will be lower than actual. Conversely, if the beams are spread further apart, then the error I calculate in this post will be higher than actual.

The important point in this study is that the beam distance be the same on the road as it is at the platform. I therefore present my measurement at the road surface.


Once again, the font is too small for this format. Click on the image to enlarge it, or simply trust me that it says 29.25", identical to the measurement at the laser platform.

If the beams are parallel, and if the platform is not moving, then I have no doubt that the Optotraffic Automated Speed Enforcement system will work properly in the situation just portrayed. Each beam will detect the same point on the truck as it passes beneath the platform, and the distance over time calculation will be spot on.  What could possibly go wrong?

Let's look at some possibilities.

Translation Error

So that you can understand the motions I am to impose on the laser platform, assume you are a thirty-two foot giant with laser eyes, you are standing erect, head up, and you are looking down at the road by moving your eyes only. You are not tilting your neck. The cars look like ants. Very big ants. With wheels.

I'm going to describe a translation as you stepping backwards while keeping your head upright, while not moving your eyes. In other words, you are no longer lasing the center of the lane. You are lasing somewhat closer to the centerline, like this:


In this example, you stepped back 1 foot. The corners of the reference lines show where the beams used to land. Now they land closer to the dividing line, by one foot. They are still separated by 29.25", and this translation will not result in a wrongful ticket.  Each beam will detect the same point on the car, they are still separated as they are at the laser platform, so there is no error associated with this translation.

If, however, the translation is too great, the beams will miss the truck entirely.

A translation can be caused in many ways. First, the cart may have been positioned too far from the curb, or the roadway was wider than Optotraffic expected, or the wind was blowing the laser platform to and fro relative the roadway. Also, if the car is not traveling down the center of the lane, but is instead traveling to the right of the lane, the effect will be the same as moving the cart too far away from the curb.

By itself, it's not clear to me that a translation can cause a false speeding ticket. However, when combined with another movement of the laser platform, it most assuredly can.

Pitch

I use the term pitch to refer to one of three possible angular rotations. Imagine instead of stepping backwards, you tilted your head down slightly. The beams from your laser eyes would strike the road closer to the centerline, just as if you had stepped backwards. Below, I show the movement of the beams due to 1 degree of nose-down pitch.


Because of your grotesque 32-foot height, tilting your nose down 1 degree causes the beams to move 9.92" closer to the centerline.

Pitch movements are, for our purpose, interchangeable with translations. From here on out, I'll ignore pitch and refer to both pitch and translation movements as a translation movement.

Roll

I use the term roll to describe the second of three possible angular rotations. To understand this one, stand in your original position, keep your head erect, tilt your eyes down as you originally did, then tilt your head to the right. Your right laser-eye will move to the right and slightly down. Your left laser eye will move to the right and slightly up. If you tilted your head sideways by 1 degree, the result on the road will look like this:


One degree of roll will move each beam 6.75" closer to the truck, assuming you tilted your freakishly large head to the right. Because the beams are still spaced 29.25" apart on the road, this will make no difference in the speed calculation. I cannot imagine the circumstances in which a roll of the laser platform will cause a speed detection error.

Don't sweat a roll error, unless it is caused by the tower oscillating back and forth parallel to the roadway. Even in that case, the problem is the movement of the platform towards or away from the car. The problem is not the roll angle that will be induced by the movement.

From here on out, I'll ignore roll issues.

Yaw

This is the one. This is the angular movement that causes problems. To understanding what I mean by yaw, assume your original position then twist your head to the side. Your right laser-eye will move to the right and back. Your left laser-eye will move to the right and forward.  If you yaw your head nose right by 7 degrees, your beams will strike the roadway like this:


This may not look serious, but it is. The beam spread is shortened from 29.25" to 29.03", but that will not produce a significant error. The problem is that the two beams will not strike the car at the same point. The rightmost beam (which will detect the car first) will hit the car to the left of the second beam. They will detect the presence of the car using different points of the car.

In the scenario shown, this will not lead to a substantial error. If, however, the beams have translated closer to the centerline (or the driver is driving closer to the right side of the lane) while the laser platform is yawed, then bad things can happen.

Let's consider a scenario in which the beams are translated 23 inches towards the centerline and the platform is yawed 10 degrees, nose right. Something bad happens with the first beam.


I show a closeup below.


The beam whiffed. It missed the body of the car completely and hit the wheel.

[Look at the detail in the Sarge 726 model. If any of you know Sarge 726, please pass along my compliments.]

Now let's see what happens with the second beam.


The second beam didn't detect the tire, as did the first beam. The second beam detected the bumper. Check the closeup.


This is a problem. When the first beam was just detecting the tire, the critical portion of the bumper was already a good portion of the way across the 29.25" spread between the beams (at least as they were spread on the road.)  Let's see how much of a head start the bumper had.


Definitely click to enlarge that last one. The fore / aft distance between the two contact points is 9.61".

Holy reduced beam spread, Batman! That is going to play hell with the speed calculation.

When the first beam is contacting the tire, the bumper contact point is only 29.25" - 9.61" = 19.64" from the second beam. The dumbass laser system doesn't know that. It calculates the speed assuming the distance is 29.25" when it is actually only 19.64".

The dumbass laser system will over calculate the speed by a factor of 29.25 / 19.64 = 1.49 = 149%. As Scooby Doo would say: "Duh Oh!"

In this case, if Sarge's pickup was traveling at 35 mph, Sarge would get a ticket for going 52 mph.

Grand Finale

We know what can cause a translation error. Lots of things. We should consider briefly what might cause a yaw error. The first and obvious possibility is that the fine folks at Optotraffic didn't park the cart parallel to the road. A second possibility is that laser platform is yawed relative to the cart. I don't recall anything on Optotraffic's amazing and colorful calibration chart showing that the cart and the laser platform are properly aligned with the roadway.

Given the flimsy nature of the bendy, twisty pole, yaw could be induced by wind. The pole will tend to twist as it bends right or left, forward or backward. The pole may also twist in response to the cable tension necessary to winch the telescoping platform to its impressive 32 foot height. There are plenty of ways in which the platform might yaw, and zero ways in which Optotraffic checks to confirm that it is not yawed.

As I said early on in this post, if you put an expensive, precision laser system on top of a bendy, twisty pole, you end up with an expensive piece of crap. Unfortunately, Optotraffic and its government clients (and protectors) are making millions and millions off Optotraffic's expensive piece of crap.

Epilogue

In the virtual world, Sarge 726 decided to fight the $40 ticket my virtual automated speed enforcer sent him. He scheduled a half-day off work, and went to the courtroom cattle call of like-minded individuals. After three hours and forty-five minutes, it was finally his time to be heard. He explained to the judge that he lived in the city, that he knew the speed trap was there, and that he was always very careful when he drove past it. He always obeyed the speed limit and never had a ticket before. But for some reason he couldn't understand, he got a ticket in the mail that said he was doing 52 mph in a 35 mph zone. He would swear under oath that he was only doing 35. He never speeds along there. Never.

The representative for the state rose and said, in a condescending voice for all the minions who couldn't understand the concept: "We use lasers calibrated against our global positioning system, Your Honor."

The judge banged his gavel on his little gavel banging thing. "I find you guilty as charged by the precision machine. You owe $40 for the ticket and $44 in court fees. We take cash or credit card. You may appeal if you wish. The fee to appeal is $80. Next."

The Impending Execution of Rodney Gray

Rodney Gray sits on Mississippi's death row awaiting execution on this second-to-last day of his life. I offer below the summary of facts as presented by the U.S. Fifth Circuit Court of Appeals.
On August 15, 1994, in Newton County, Mississippi, Grace Blackwell, the 79-year old murder victim, drove to her local bank and proceeded to the drive-through window. Arlene McCree was working as a bank teller, and Blackwell had been her customer since 1980. McCree thought Blackwell looked “terrible.” Usually, McCree and Blackwell would engage in small talk;  however, on this occasion, Blackwell would not look at or converse with McCree. Instead, Blackwell simply stated “I need twelve hundred dollars.” McCree had to prompt Blackwell by asking her whether she wanted to cash a check or use a withdrawal slip. In response, Blackwell threw a blank check into the window tray. McCree could not see the backseat of the car because there were clothes “hanging in a very unusual manner.” Concerned by Blackwell's behavior, McCree asked Blackwell whether “something [was] wrong or ․ someone [was] in the car with her.” Blackwell did not respond to the questions;  instead, she attempted to mouth words to McCree, who could not read Blackwell's lips. After McCree made out the check for $1200, Blackwell signed it. Although McCree attempted to stall the transaction, she subsequently placed the money in the window tray, and Blackwell grabbed it. Blackwell then drove away saying “I'm hurrying, I'm hurrying.” McCree did not think that Blackwell was speaking to her. Believing Blackwell had been taken hostage, McCree called the Sheriff's Office.

A deputy sheriff was dispatched to Blackwell's home and found the front door open. Blackwell's car was not there and the “telephone wires [were] disconnected.” Meanwhile, Harry Jones was driving his car on Pine Bluff Road in Newton County and saw a brown Chrysler, which he later identified at trial as Blackwell's car, stopped in the road. He saw a man “wrestling with this lady.” Although he could not identify the woman, he identified Gray as the driver of Blackwell's car.

Later that same day, Lane McDill was driving to town on Newly Road 1 in Newton County and observed something lying “just off the bridge on the right-hand side of the road.” McDill stopped his vehicle and quickly discovered it was a deceased woman. He then drove to town and notified the police that there was a body at the bridge. As a result, law enforcement officers arrived at the scene, and the ensuing investigation revealed that Blackwell had been killed by a shotgun wound to the face. A forensic pathologist determined that Blackwell suffered a “series of injuries,” “including the presence of two shotgun wounds, as well as multiple scrapes of the skin, called abrasions, and lacerations, a cut, and contusions.” The lethal shotgun wound was a “contact shotgun wound with the muzzle of the shotgun placed against the area of the mouth.” The second shotgun wound “is consistent with having gone through an intermediate target scattering and striking the decedent over the left arm, left chest, and left cheek.” Blackwell's other injuries were consistent with either being struck by or pushed out of a vehicle. The forensic investigation also revealed that Blackwell had been raped and that the DNA analysis indicated that Gray was the perpetrator.
[Testimony regarding the DNA match: The “significance of [the] match is that there is a probability that selecting someone other than, someone unrelated to [Gray] in the population, having the same profiles as that sample, would be less than 1 in 446,000,000 in Black, Caucasian, and Hispanic populations.”]

Additionally, the Newton County Sheriff's Office interviewed Mildred Curry, who was Gray's girlfriend at the time. Curry told them that Gray had called from jail and informed her that there was money in her bathroom vent. A deputy sheriff searched her residence and found $1,123 in the bathroom vent. The search also uncovered the clothes and boots that Gray was wearing on the day of the murder.
I find no claim by anyone, even Rodney Gray himself, that he did not commit the crime. I therefore stand mute on his execution.

Errata:
I was wrong when I wrote that Rodney Gray did not proclaim his innocence. This article about his execution indicates that he proclaimed his innocence until the end.

Saturday, May 14, 2011

The Impending Execution of Daniel Bedford

Daniel Bedford sits on death row, awaiting execution by the people of Ohio. I offer the following summary from the US Sixth Circuit Court of Appeals, Daniel Bedford v. Terry Collins. I have eliminated most of the legal references without adding ellipses.
A jury convicted Daniel Bedford of the aggravated murder of Gwen Toepfert and the murder of John Smith, and at the jury’s recommendation a state trial court sentenced him to death. The Ohio courts affirmed his convictions and sentence on direct review and denied postconviction relief. Bedford sought a writ of habeas corpus under 28 U.S.C. § 2254, which the district court denied. We affirm.
As a side note, we are the publishers of Smith's Guide to Habeas Corpus Relief for State Prisoners under 28 U.S.C. §2254. In the hopefully unlikely event you find yourself in need of understanding the process of filing a Habeas Corpus petition, click the appropriate icon along the right-hand sidebar of this august blog.
In 1978, Bedford met Toepfert, whose father owned the bar where Bedford worked, and for the next several years the two were involved in an “on-again, off-again” relationship. By 1984, they were estranged.

Bedford’s feelings for Toepfert remained, however, prompting him to try to “rekindle [their] prior romance.” On April 21, 1984, he visited her apartment bearing a gift and hoping to make amends -- only to learn that Toepfert’s new boyfriend, John Smith, was already there. Three days later, Bedford tried again. At around 2:30 a.m. on Tuesday, April 24, Bedford, who had spent the evening working at one bar and patronizing another, telephoned Toepfert’s apartment -- only to learn from her roommate, Jo Ann Funk, that Toepfert was asleep and that Smith was with her.

Later that morning, Funk woke to the sounds of “gunshots and screams.” Apparently overcome by Toepfert’s rejection, Bedford entered her apartment armed with a .38 revolver and a shotgun, shot Smith after a brief struggle and shot Toepfert. During the melee, Toepfert ran into Funk’s bedroom, screaming that she had been shot. Bedford found her there and shot her again with the revolver and the shotgun. Smith and Toepfert died from the gunshots.

Bedford fled to Tennessee. Once there, he visited an acquaintance, to whom he confessed his crime, and who reported Bedford to the police. After Tennessee police arrested Bedford (and Mirandized him), he gave a statement admitting the crimes and eventually gave a similar statement to Cincinnati authorities.
I find nothing intrinsically suspicious about the state's explanation of the crime. I find no one making claims of actual innocence for Daniel Bedford. Not even Bedford himself claims he did not kill Gwen Toepfert. His defense during his trial was that his crime was not pre-meditated, that it was an unplanned outburst fueled by alcohol and emotion. His argument is mentioned in the Sixth Circuit's decision as the court discounted his claim that the prosecutor's closing argument was improper.
Bedford complains about comments by the prosecutor in closing argument at the guilt phase that allegedly disparaged defense counsel’s tactics. The prosecutor called “[s]ome” of Bedford’s “arguments” “Mickey Mouse defenses,” and he characterized others as attempts to “confuse” the jury by “fill[ing] the courtroom with as much smoke as you possibly can,” casting aspersions “all around the courtroom” and putting “everyone on trial in the case except our little boy over here” -- all in the hope that the jury would “lose sight of the real issues in the case.” Attempting to deflate an attempt by the defense to discredit a particular government witness, the prosecutor also predicted that the witness would “be dragged through the mud by the defense.”
These comments were not improper. The prosecution necessarily has “wide latitude” during closing argument to respond to the defense’s strategies, evidence and arguments. How far the government may go, true enough, depends on what the defense has said or done (or likely will say or do). And in all events the prosecutor may not simply belittle the defense’s witnesses or deride legitimate defenses, nor may he offer his own opinion about a witness’s credibility. But the prosecutor’s remarks in this case -- all made in the course of the fastmoving thrust and parry of a criminal trial -- did no more than respond to Bedford’s actual and reasonably likely contentions and tactics.

Several of the prosecutor’s comments, Bedford adds, were calculated to incite the jury’s passions and were engineered to elicit an emotional, not a reasoned, reaction to the evidence. Responding to the defense theory that Bedford’s conduct was the culmination of an unplanned outburst -- fueled by alcohol and emotion and sparked by a life-threatening confrontation with Toepfert’s new paramour -- the prosecutor argued: (1) that the evidence, including graphic photographs of Toepfert’s and Smith’s bodies, proved Bedford’s conduct was purposeful and planned; (2) that Bedford’s inner “demon” -- his alcohol dependence -- was not responsible for his behavior, as the only “demon in this case” was Bedford and (3) that the jurors’ duty required finding Bedford guilty and that, if they did so, each juror could say to himself “I did Gwen justice and I did Johnny justice.”
These comments did not deprive Bedford of a fair trial. By alluding to the victim photographs, already admitted into evidence, and arguing that they established Bedford’s intent, the prosecutor permissibly sought to draw an inference from the evidence. Calling Bedford a “demon” comes closer to the line -- it was unnecessary and unprofessional -- but it goes no further than similar comments that have not required setting aside a state conviction. See Olsen v. McFaul (holding that prosecutor’s deliberate, repeated references to defendant as a “deadbeat,” a “thief,” a “creep” and a “liar” did not violate due process); see also Byrd (regarding prosecutor’s repeated references to defendant as a “predator”).
Apparently, according to the U.S. Sixth Circuit Court of Appeals, the prosecutor may not "offer his own opinion about a witness’s credibility" but he can call the defendant a "liar." Welcome to the U.S. justice system.

Discussing prosecutorial misconduct is way, way, way, way, way beyond the scope of this modest post. Here I will merely observe that the court (in its desire not to overturn a case) has done nothing to discourage prosecutors from relying of theatrics and passion rather than evidence. In my not so humble opinion, closing arguments should be limited to discussion of facts. Alternatively, they should be forbidden altogether. Allowing either the state or defense attorneys descend to name-calling, character assassination, invectives demeans our justice system.

If the prosecutors can prove their case on facts alone, they should do so. If the prosecutors cannot prove their case on facts alone, the verdict should be "not guilty." In either case, prosecutors should not be allowed to  supplement evidence with disparagement and inflammation of the jury.

The U.S. Sixth Circuit Court of Appeals once again encouraged prosecutor misconduct when they should have sanctioned it. They thereby increased the risk that defendants will be convicted by showmanship, passion, and fear rather than facts and considered deliberation. They have increased the risk of wrongful convictions.

Since I ration my resources for those cases in which a defendant or prisoner is factually innocent of the crime for which they are charged or convicted, I stand mute with respect to the execution of Daniel Bedford, with an exception. I object to the prosecutors conduct in this case and to the Sixth Circuit Court's endorsement of that conduct.

Monday, May 9, 2011

Automating Wrongful Convictions: Petard Hoisting In Maryland

From The Free Dictionary, we learn that petard means "a small bell-shaped bomb used to breach a gate or wall." The word is from the French peter, meaning to break wind, which is from the French word pet, a breaking of the wind, from the Latin word peditum (neuter past principle of pedere), to break wind.

We learn further of the word's history:
The French used p├ętard, "a loud discharge of intestinal gas," for a kind of infernal engine for blasting through the gates of a city. "To be hoisted by one's own petard," a now proverbial phrase apparently originating with Shakespeare's Hamlet (around 1604) not long after the word entered English (around 1598), means "to blow oneself up with one's own bomb, be undone by one's own devices." The French noun pet, "fart," developed regularly from the Latin noun pditum, from the Indo-European root *pezd-, "fart."
The fine folks at Optotraffic have blown themselves up with their own devices. Either that or they have farted. I'll allow them to choose.

TFFAO (The Fine Folks at Optotraffic) have mounted a somewhat less than stout defense of their system. Clearly they are bothered by Will Foreman's success in court. Most assuredly (I tell myself) they are deeply  scarred by my pithy observations in Demons Devices from Hell, Lasers Gone Wild, and The Empire Strikes Back. I should have used the last title for this post, but I panicked. Now I'm becoming concerned that if TFFAO don't give up soon, I'll run out of clever sub-titles.

Optotraffic presented its case recently in both a textual and video format. I'll first critique select portions of the textual defense. Hang on. Here we go. 
How Optotraffic's Laser Sensor Speed System Works
That's not a very flamboyant title. They could have generated more hits by using something more colorful. I offer the following titles free of charge.
1. Speed Kills. Lack of Speed Kills our Profits.
2. Lasers, SI!   Bendy Poles, NO!
3. Please, Please, Please Don't Use the Photos as We Suggested
The last one isn't particularly clever, but the hour is late and I'm tired.
Like their other speed sensor units in Maryland, the unit in Forrest Heights ...
It's Forest Heights, with one r. It's not Forrest "Gump" Heights, with two r's. You shouldn't make such silly mistakes when you are trying to convince people that you don't make mistakes. 

Uh, oh!  I feel myself being overwhelmed by a cultural reference.

In the touching scene below, entitled "Run, Forrest, Run," Forrest Gump ran right out of his leg braces trying to get away from bullies.


In a seldom viewed out-take, Forrest was clocked by an Optotraffic DLS-10S Automated Speed Enforcement device doing 76 in a 35 mph zone. The system took two images of his butt and mailed them to him, along with a ticket for $40.

But I digress.

Let's see if I can finish the first sentence without getting further distracted.
Like their other speed sensor units in Maryland, the unit in Forrest Heights, [sic] MD. has two laser sensors, some centimeters apart, that employ light detection and ranging technology in a "laser pointer type" fashion.
I don't think MD. needed a period after it. The period made the sentence seem as if it ended prematurely.

I see they use two laser sensors "some centimeters apart."  Wow. WOW!

(Psst! You folks at Optotraffic. Any two items are "some centimeters apart," even if only zero centimeters apart.  Unless you specify how many, you're not communicating.)

Regarding their description of how the system works, I can envision the author using finger quotes when he/she informs us, the unwashed masses, that their system works in "laser pointer type" fashion. Now I finally get it. Thanks, Optotraffic.
These two beams, one further "downstream" from the other, are perpendicular to the lanes of traffic.
The quotes around "downstream" are unnecessary and unimpressive.
Using laser beams, they precisely measure the presence of an object 10,000 times PER SECOND for as long as it takes to travel between the two.
The "laser pointer type" lasers just don't fire 10,000 times per second, they fire 10,000 times PER SECOND. Hopefully TFFAO will never, ever again try to impress us with their awesome caps locking capability.
The speed is precisely measured BY THE LASER SENSORS ...
Jeez Louise!
The speed is precisely measured BY THE LASER SENSORS from the time a vehicle hits the first beam to the time it hits the second beam. The units are calibrated daily, using GPS -- the most accurate means available today, and are removed and tested annually in an independent testing lab. This laser sensor system is believed to be the state-of-the-art in terms of accuracy and precision.
They are mightily impressed with their LASER SENSORS, as they should be. I have no doubt that Optotraffic, a sub-division of Sigma Space Systems, is spectacularly good at building lasers. I also have no doubt that they can and do calibrate their laser firing rate daily against GPS pulses. Nonetheless, There  is compelling evidence that their system is not working.

Though the laser firing portion of their system may be top notch, there must be some other problem causing the well documented wrongful tickets. I have suggested (as possible sources of error) bendy poles (due to wind), cross-eyed (misaligned) lasers, near-sighted lasers (which are differentially unsure how far away the ground is), and astigmatic lasers (which must augment their time delay detection with signal strength change detection.)

None of these other potential sources of error have anything to do with how well calibrated the laser pulse rate is. Yet TFFAO refuse to even mention any potential source of error other than lasers firing too quickly or too slowly, which they would never do, and we have the daily GPS calibrations to prove it, dagnabbit!

If Optotraffic could explain why bendy poles or cross-eyed lasers cannot cause gross errors, I suspect they would do so. I expect instead that they will rely on the "We Fire Lasers 10,000 Times A Second" explanation until 10,000 cows come home.
The speed of cars is NOT determined by cameras in Forrest [sic] Heights or in any of the other Maryland jurisdictions using Optotraffic’s system. It is determined solely by the laser light sensors. This fact is at odds with ... how one chronic Maryland speeder -- a crusader against speed sensors, has represented ... the speed sensor system that is actually used in Forrest [sic] Heights;
Whoa! I believe they might be speaking of Will Foreman when they refer to "one chronic Maryland speeder." Will Foreman, after all, lives in Maryland. Furthermore, his employees have been given 40 or so tickets by the fine folks at Forest Heights. Maybe I'm just imagining things.
In Maryland media and the courts, this chronic speeder is using time stamped still photos to seek to call into question the accuracy of the speed sensor measurements in Forrest [sic] Heights. According to media statements, this individual or his company have received more than 40 speeding citations in the last year, the majority of which have been in a Forrest [sic] Heights’ school zone. This individual argued that the time and distance travelled between the two time stamps show he had to have been moving slowly -- ie., [sic] that the time stamp and camera shot of his actual location/distance were equal in precision. This is false and factually wrong.
Just a minute while I check Dictionary.Reference.com. I'll be right back.

Okay, I'm back. I found what I was looking for. Here it is.

Libel: defamation by written or printed words, pictures, or in any form other than by spoken words or gestures; anything that is defamatory or that maliciously or damagingly misrepresents.

Optotraffic once again refers to Will Foreman as a chronic speeder. They even make it clear they are talking about Will Foreman, since he is the only individual or company in the news with more than 40 speeding citations, the majority of which have been in Forest Heights. I immediately recognized Will Foreman as the chronic speeder of whom they were speaking.

Not only is Will Foreman not a chronic speeder, he is not even a one-time speeder, at least as far as our judicial system is concerned. Foreman has won the first 5 of the 40 cases which he will have heard in court. Not only that, I don't believe Foreman was even in the vehicle for any of the tickets issued. The vehicles were company vehicles driven by his employees.

I certainly thought less of Mr. Foreman after reading those paragraphs. Had I relied only on the word of the fine folks at Optotraffic, I would have vowed to never set foot in Mr. Foreman's business. Ever. Only through the power of the Internet did I learned that the smear campaign was merely a case of Optotraffic defaming Will Foreman with misrepresentations in a form other than spoken words or gestures.

Prepare yourself for the second grand claim of their defense. Remember, the first one is Lasers firing 10,000 times PER SECOND, calibrated daily with GPS.
Still photos cannot be used, and are not used, to measure speed because of built in delays in the camera mechanisms and functions including shutters. In actual practice, the time stamp and still photo of where the car is located do NOT match.
I won't waste my time falsifying this grand claim. I'll allow Optotraffic to do it themselves. I'll allow them to be hoisted with their own petard. The following quotes are from their own brochure.
The innovative and non-invasive sensor determines with high accuracy the vehicle speed and triggers a digital still camera. Since a stationary object is present along with the vehicle, a photographic method also determines speed, guaranteeing fairness.

While the primary evidence for issuing a speeding citation is the calibrated lane sensor, the two photos provide the secondary evidence of speeding that is presented to the citation recipient.
The sound you hear is the sound of Optotraffic's head exploding.

That petard like explosion provides a nice segue to Optotraffic's professionally produced video, here. When editing the video, they apparently realized they wrote in their brochure that you can in fact use the cameras to determine speed. In the video they cleverly tap-danced around the issue. They make it seem as if you can't use the photos, but actually say only that they don't and won't rely on the photos.
My name is Mario Bohorquez. I am the Chief Commercial Officer for Optotraffic. The citizen who received the citations issued by one of our clients claims that he can use photographic pictures, two pictures, to determine his vehicle's speed when the citation was issued.
Mr. Bohorquez was sitting in front of an array of brightly lit instrumentation. Notice that he did not say, at least on the video, that you could not or should not determine speed from the photos. Just as he was about to begin his second sentence, the video cuts away to what has become known as the Forest Heights Toll Road. Other than that single interrupted thought, we never hear from Mr. Bohorquez again. Instead, Lt. C. Washington of the Forest Heights Police Department picks up the thread.
Some of the concerns were that the photos determined the speed and that's not the way we measure the speed. We measure with the Lidar system, not the photos. The photos are simply to show that the vehicles were there on the time and date of the violation, get owner information from the rear license plate, and to prove that the vehicle was in motion.
Lt. Washington never says that the photos could not or should not be used to determine speed, only that they never use them. Just as a reminder to one and all, I excerpt an excerpt from the Optotraffic brochure.
... a photographic method also determines speed, guaranteeing fairness.
I think Optotraffic is breaking wind.


P.S.
For even better petard hoisting, read this post at the Stop Big Brother Maryland web site. It is quite nicely done. For information straight from the chronic speeder himself, visit Will Foreman's Facebook page.

Sunday, May 8, 2011

The Impending Execution of Benny Stevens

Benny Stevens sits on death row. On Tuesday, the people of Mississippi will execute him. I have reviewed Stevens' case, as I have reviewed each execution this year, and I find no reasonable possibility that Benny Stevens is factually innocent of the crimes for which he is to die.

From the Mississippi Supreme Court decision in the case of Benny Joe Stevens v. State of Mississippi, I offer the State's summary of his crime. I exclude, without ellipses, the legal references.
Benny Joe Stevens was charged with the shooting deaths of his ex-wife, her husband and two children. Stevens was convicted of four counts of capital murder on December 4, 1999, and sentenced to death on all four counts. The convictions and sentences were affirmed by this Court. Stevens has now filed his application for post-conviction relief.
The murders of Wesley Reid, Glenda Reid, Heath Pounds and Dylan Lee, as well as the aggravated assault of Erica Stevens, took place on Sunday, October 18, 1998, in Marion County. Erica is the daughter of Benny Joe Stevens, and she lived with her mother, Glenda Reid, with her stepfather, Wesley Reid, and her brother, Dylan, in a trailer home in Marion County located on Shiloh Firetower Road in Foxworth, Mississippi. Glenda and Stevens had divorced when Erica was three years old. Benny Joe Stevens subsequently married Lauren Stevens ("Lauren") in 1993 and thereafter gained custody of his daughters, Erica and Angela, in 1996. However, in August of 1998, Glenda regained custody of Erica. ...

On Sunday, October 18, 1998, ... Lauren entered Stevens's bedroom, she saw her husband with his gun belt laid out on the bed and putting shotgun shells in the gun belt. Lauren also remembered seeing his .357 handgun. Stevens then took his guns and left the home in his truck.

On Sunday, October 18, 1998, Erica, Heath, Wesley, Glenda and Dylan were all at the trailer and had finished eating supper when Erica saw Stevens park his truck beside Wesley's truck in the backyard. No one was with Stevens. Erica saw Stevens get out of his truck. According to Erica, Wesley opened the sliding glass back door wide enough to stick his head out the door and called, "Benny Joe, Can I help you?" Erica then heard a gunshot and Wesley scream, "[S]hit, he shot me." Erica tried to rescue her brother and his friend but Stevens shot her in the back. She then hid in the trailer's master bath and watched helplessly as her mother was shot by Stevens. She then heard Benny Joe say, "[B]itch, I told you that I'd kill you one of these days."

Erica climbed through a small window in the bathroom where she had been hiding and heard more gunshots while she was running away from the trailer. Erica went to a neighbor's house for help and collapsed at the door. Erica told the neighbors that her father had shot her mother, stepfather, brother and friend. Stevens returned to his home where his wife inquired, "[W]hat did you do?", to which Stevens replied, "I just killed a family."
For a more detailed and more grisly recitation of the States' case, see an earlier ruling by the Mississippi Supreme Court.

I find nothing in the States' summary which suggests to me that Stevens may be factually innocent.

I find not a single organization or person who suggests that Stevens may be innocent.

I therefore stand mute regarding the execution of Benny Stevens.

Friday, May 6, 2011

Automating Wrongful Convictions: The Empire Strikes Back

Two months ago, I published the first of eight posts on Eric King. I believed there was an outside chance that facts and evidence could spare his life. I was naive and wrong. Arizona executed Eric King for a crime he probably did not commit. Eric King is still dead, and I'm still bummed.

Two weeks ago, I published my first post ever regarding speeding tickets. I have since written a second. I'm admittedly more sanguine and jocular about those tickets than I am about Eric King, or Cameron Todd Willingham, or Byron Case, or Michael Ledford, or Cory Maye, or [insert very long list here.]

Will Foreman, the folks at Stop Big Government Maryland, and reader / commenter Al Smith, on the other hand, are considerably more bummed about the tickets. Will Foreman has been beating Maryland up in the courtroom. Stop Big Government Maryland has been beating Maryland up online. Reader / commenter Al Smith deviously linked his name to a company that sells GPS Camera Detectors.

I'm pleased to see a public aroused by injustice. I join the rabble for two reasons. First, it's more pleasant writing about people being wrongfully deprived of their dollars rather than their freedom or their life.

Second, I see the injustice associated with wrongful speeding tickets to be a microcosm of our country's wrongful conviction problem. The process in each situation is similar.
Charge someone who is innocent
Presume the person is guilty
Ignore, hide, never find, or otherwise exclude exculpatory evidence
Rely on evidence known to be unreliable
Relieve the state of its burden of proof
Convict
I calculate that more than 10% of the 2.5 million people we have behind bars have been wrongfully convicted in such fashion. That's more than a quarter million of our countrymen that we have seriously, seriously wronged.

Not to worry, though. It can never happen to you. Or your loved ones. 

The Empire Strikes Back 

The Maryland Towns of Cheverly and Forest "One Community - Many Cultures" Heights have posted a defense of their Demon Devices from Hell "automated speed enforcers." The two posts are nearly identical, so much so that they were likely written by a third party. While the names Optotraffic and Sigma Space Systems come to mind as possible ghost writers, the author at this point remains shadowy. (That sounds more ominous than unidentified.)

You can follow the two links if you wish to see how similar the two posts are. Alternatively you can trust me. In either case, I'll repeat the Forest Heights post below, interrupting only occasionally to offer constructive criticism.

Ready? Good. Settle in, buckle up, here we go.
SPEED CAMERA PROGRAM VERIFICATION ANALYSIS
Recently some citizens have raised concerns regarding the accuracy of Forest Heights Speed Camera Program that was instituted on May 1, 2010. The Mayor, Council, and Police Chief take these concerns seriously, as it is critical that citizens have confidence that the Speed Camera Program is operating correctly. Over the last week town officials have reviewed public concerns and instituted an independent verification process. Below is an overview of how well the Town’s speed camera equipment operates.
It would have been nice if the "town officials" had better explained what they meant by "independent verification." Does "independent" mean merely that the "town officials" did not conduct the analysis? Is it possible that the "independent" review was conducted by the fine folks at Optotraffic or Sigma Space Systems. They are, after all, the ones who allegedly know how the system works.

Note also that the independent review took less than a week. Part of "the last week" was taken by town officials reviewing public concerns. Part was then taken by instituting an independent verification process. (It's almost as if they knew who to contact and contract for such a quick and thorough review.) Part of the week was then consumed by the independent analysis. The remainder must have been spent preparing the unattributed report, which just coincidentally mimicked the unattributed report published last year by the Town of Cheverly, who had "over the last 10 days ... reviewed resident concerns and instituted an independent verification process."

Imagine that.

So here's a constructive criticism. If you are going to assure everyone that everything is okay, and you are going to rely on a supposedly "independent" analysis to do so, you should probably at least mention the name of the person or organization who did the analysis.

Let's continue.
HOW THE EQUIPMENT OPERATES:
The speed camera unit used by the Town of Forest Heights, supplied by Optotraffic, utilizes Lidar technology for speed detection coupled with a camera for capturing vehicle information. Lidar is a speed detection technology that utilizes a laser beam to determine the distance to the target vehicle by calculating the time it takes for the beam to reflect off of the vehicle and return to the unit. As a vehicle approaches the unit the distance changes, the change in distance and time are the variables used to determine the target vehicle's speed. In the case of Forest Heights’ Lidar, the equipment is recalibrated daily to ensure the equipment that makes this distance/time calculation is accurate.
Welcome to the world of half-truths. While it is true that the system fires lasers at cars and measures the time for the beams to return, the independent reviewer forgot to tell you that the system also works by attempting to detect changes in signal strength. I guess the independent reviewer didn't check the patent. I did. Here you go.
Using the recorded delay in conjunction with the signal strength, the presence/absence of a vehicle can be determined. ... If the recorded signal strength is different from the expected value, and/or the time delay is smaller than the one corresponding to the road surface, then trigger the timer to start .. or stop.
The laser ranging system clearly has a problem. That's why they augment it with  variable power detection. Sometimes the system will  rely on how bright something is rather than how far away it is. If you put such a system in a darkened cave and shine two lights at it from random distances, it will always think the 100 watt bulb is closer than the 60 watt bulb, because the detection system was made stupid by the variable-signal-strength feature.

If the system could depend on just its laser ranging capability, then it would. There would be no need to complicate everything with some sort of unproven "I have seen the light" system. Conversely, if the signal strength system was entirely dependable, there would be no need to augment it with the laser ranging system. The fact that they are using both methods tells me that they are not completely confident in either.

It's not that a laser system can't detect a variable signal strength, it's that it will be very difficult for the two lasers to detect within the same tolerance. One might trigger where the car is slightly reflective and the other might not. One might detect the car because the beam got brighter, and the other because the beam took longer to return. In that case, they would be looking at different parts of the car. That's bad.


Let's continue.
Lidar calculates the speed of an approaching vehicle beginning at a point 50 feet prior to the unit, where laser beams strike an approaching target vehicle at two defined locations.
That's incorrect. The laser beams look downward, not up or down the road. Once again, a peek at the patent would reveal that.  I'll include an image from the patent below, just in case anyone from the independent review team happens to read this post.


See. The lasers point down, not up the road. I suspect the well-informed independent review team was just confused because the system snaps images of "speeders" after they pass through the beams. I quote from the news article that first loosed me on this story.
Optotraffic representatives said the photos are not intended to capture the actual act of speeding, and are taken nearly 50 feet down the road from sensors as a way to prove the vehicle was on the road.
Oops. They can't even get their talking points straight. Oh well, back to Forest Heights' report of their independent review.
When the unit calculates the speed of a violator, and determines that the speed is in excess of 12 mph above the posted speed ...
Sorry. I didn't make it very far before feeling the need to interrupt again.

Is the unit calculating the speed only of violators? According to the sentence, the unit first calculates the speed of a violator then determines whether the speed was in excess of 12 mph. But the unit doesn't know if the person is a violator until after the speed has been determined to exceed the 12 mph threshold. It's a subtle point. I'll grant you that. It was an unforced error though, one that reveals a tendency to assume guilt and give a fair trail (or calculation) later. The sentence could have been more precisely written thus:
When the unit calculates a speed in excess of 12 mph above the posted speed, ...
See. Okay, I'll back up and let Forest Heights complete a paragraph before I interrupt again.
When the unit calculates the speed of a violator, and determines the speed is in excess of 12 mph above the posted speed, two different camera photographs are then made of the target vehicle after it passes the unit. These photographs are not used to calculate the speed of the vehicle, but are used for two essential purposes. The first is to capture the rear registration plate number of the vehicle (since not all States require a front plate) and the second purpose is to prove the vehicle was in motion at the time of the incident. Occasionally it is suggested by the violator that the vehicle is parked or standing. A citation is subsequently issued to the vehicle owner, as required by law, only after it is verified that there is direct visual evidence of the vehicle owner’s registration plate displayed on the vehicle.
I'll withhold comment on the photos, for now.
SYSTEM IS ACCURATE
CALIBRATION:
The Optotraffic equipment runs a self- calibration test every morning. An Optotraffic Technician and a Forest Heights Police Officer meet daily at the unit to review the results. Therefore, as standard practice, the equipment is verified every day.
I include one of their calibrations below, for your perusal at their distress. Click to enlarge. Click twice to enlarge even more.


Try not be be unduly impressed by plots, colors, and jargon. This is a public relations report. It's intended to look impressive and it's intended to give them cover. It identifies the unit, gives dates and locations, and lets the reader know that the battery was working. It shows a GPS satellite map because that's really, really impressive. The meat of the calibration, to the extent there is any meat on that bone, is the second plot from the bottom. It shows that the lasers are firing at 10,001 hertz. That means you are being lased 10,001 times per second by two lasers as you pass beneath this unit.

The nominal beam rate is 10,000 hertz. The allowable rate is anywhere within 2 hertz (cycles per second) of 10,000. The unit being calibrated is within 1 hertz, based on pulses being transmitted by our GPS satellites.

The bottom most plot converts the 1 hertz error into an mph error. That's all. It shows that a one hertz error is equivalent to an error around 0.1 mph, if the car is going 35 mph.  That's pretty impressive accuracy. That's why they show this plot.

This isn't even a half-truth, however. It's closer to a one-tenth truth. The fine folks at Optotraffic, and Forest Heights, and the Town of Cheverly, and those who did the independent review, never mention that there are many other possible sources of error in the system, sources that are not addresses in the shiny plot.

I discussed (in painful detail) eight possible sources of error in Automating Wrongful Convictions: Lasers Gone Wild. I'm independent. I'm (unfortunately) uncontaminated by money for my writing on this blog. I published the results of my independent survey on 28 April, just about the time the Forest Heights "town officials" were looking for an independent reviewer.

I suspect, though, that the "town officials" have never heard of me or this blog. I'm guessing even if they had, they would not want me explaining to them how their units may have a problem. I'm certain they wouldn't want to hear that they probably have a bendy pole problem. I mean of course, that their unit sways in the wind. That corrupts the reading.

They might also have a cross-eyed laser problem. I'm surprised the independent review team didn't mention it, given that the issue is mentioned in Optotraffic's brochure.
Each lane sensor is third party calibrated annually (by Maryland law) to verify the beam distance.
The beams must be parallel. The uproad / downroad distance between the beams at the road must be the same as the uproad / downroad distance at the laser mount. If the lasers are 35 feet from the road and 24 inches apart at the mount, and if they converge by only 1 degree, the beam distance at the road will be only 16.67 inches. That will cause a serious error in the speed calculation. If you were traveling 35 in a 35 zone, you would get a ticket for traveling 50 miles per hour.

Optotraffic should show the yearly beam distance calibrations for each unit. They should also address the other multiple sources of potential error for their system, particularly the problem of poles swaying in the wind. To repeatedly spout the limited mantra about being GPS calibrated, and to consistently suggest that it is the entire story, is to be patently dishonest.
OVERALL PROGRAM RESULTS:
Since its inception the speed camera program "Operation Get Home Safe" has issued a total of 72,808 tickets, for an average of 5 days a week during the 12 month period it has been in operation. Based on previous measures, more than 10,000 cars travel north and south bound each day on Hwy 210. This means that less than .03% of cars have received tickets exceeding the posted speed limit of 35 mph by more than 12 mph.
Now this is simply pathetic.  From this point on, I'm going to have to speak to Forest Heights' "town officials" directly.

Listen up: 10,000 cars a day, 5 days a week for 52 weeks is 2,600,000 cars. 72,808 tickets divided by 2,600,000 cars is 0.028, which is definitely less than 0.03 which is definitely NOT 0.03%. It's 3%, you dimbulb.

Jeez!

Now assume someone drives your road both directions, five times a week for 52 weeks. That's 520 one-way trips. Now, 3% (not 0.03% you dimbulb) of 520 trips is 15.6 tickets per year per driver, on average. You are ticketing each driver at an average rate of approximately 1 ticket per month. Seems like a lot to me.

But I digress. Back to your defense of your Optotraffic system.
Clearly this does not very the results of a specific ticket, but it does indicate that the equipment is not generating an abnormal number of tickets.
I'm sure you meant "verify the results," not "very the results." If you are trying to make a case that you could not have made a mistake with the tickets, you are doing a bad job.
Furthermore the average number of tickets per month have dropped from 16,575 per month initially to 4,892 recently, average speed of violators has dropped from 57 mph to 50.
By recently, do you mean after Will Foreman's employees (and others) decided they could avoid tickets only by driving around, rather than through, your town. I notice that you earlier wrote "based on previous measures, more than 10,000 cars" traveled north and south each day. I wonder how many cars pass that way now, now that your street has become known as the Forest Heights Toll Road.

Clearly you didn't intend for the number of tickets to drop off. That wasn't your hope or expectation, was it? I mean, after all, you budgeted more for tickets in your FY2011 budget than your entire FY2010 budget. You budgeted more than $1000 in speeding tickets per each Forest Heights' resident. Come on, admit it. It's not about safety. It's about money. Isn't it?

Also suspicious is your claim that the average speed has dropped from 57 mph to 50. Let me check my math. I'll be back in a moment.

Yep, 57 mph is 22 mph greater than the 35 mph speed limit you mentioned earlier. You allegedly put these things in school zones, though that term seems flexible when you want to collection traffic fines improve safety. Anyway, last I checked, 22 mph above the speed limit is more than the 12 mph threshold. So why is the average person not getting a ticket?  How can the average speed be between 50 and 57 mph in a 35 mph zone, and you ticket only 3% (not 0.03%, you dimbulb) of the drivers? Something seems wrong here.

If you sense that I am getting frustrated with the crappola, you're right. I run into this kind of crappy work all the time when I am looking at how someone got put away for life, or how someone got lethally needled by the State. It bugs the hell out of me.

But I digress.
The number of accident reports for the intersection of Hwy 210 and Livingston Road has also dropped significantly. Overall this shows that the program is working and drivers are reducing their speed in this particular school zone.
Perhaps the accidents dropped because people stopped driving down your toll road. Perhaps the intersection is the only place where traffic accidents dropped while all other locations showed substantial increases. If you can show that accidents consistently dropped in those locations where the devices operated, when the devices operated, and the accidents consistently did not drop in other locations, you might then be able to make a case that the devices reduce accidents. Simply claiming that they reduce accidents on one corner, without providing any data whatsoever, is just more of the same crap. You ask that everyone to simply trust you, at the same time you are giving people reason not to trust you.

By the way, even if the devices do reduce accidents, that is no excuse for wrongfully ticketing the citizenry.
TICKET PHOTOS DO NOT SHOW SPEED:
One citizen argued that his own tickets images were evidence that proved the equipment was operating incorrectly. According to his measurements the photos indicated his car had only travelled 24 feet between the first and second photo. He erroneously claimed that the elapsed time between the photos was .461 seconds indicating that the car was travelling at approximately 36MPH based on his calculation of velocity as a function of distance over time. Response: The photos generated by the camera and printed on the citation are never used to determine the speed of the vehicle. As stated above, the photos are taken after the vehicle passes the device in order to capture the license plate of the vehicle, and to prove the vehicle was actually moving if it is needed in court. The speed of the vehicle is calculated by a “laser” not a photo as the vehicle approaches the unit, 50 feet prior to passing the unit.
I'm not aware of anyone suggesting that the system is calculating their speed based on the photo. If  the system did, we probably wouldn't be having this discussion. Instead, your victims are using the superimposed images as a means of showing that your system is calculating their speed incorrectly.

You don't have to be Einstein or Sherlock Holmes to know, to absolutely know, that the photos show your camera system is failing.  Check the two composite images below. They are from tickets you sent Will Foreman for his company vehicles.



The trucks in the two composite photos are the same length. As it turns out, the time between the images in each composite photo is 0.363 seconds. The trucks are separated by nearly the same distance. They must be going nearly the same speed if they cover nearly the same distance in the same time. If anything, the truck in the upper image is traveling slightly faster than the truck in the lower image. However ...

You claim the truck in the upper photo is going 56 mph. You claim the truck in the lower photo is going 76 mph.

It can't be. It simply can't be. Fire your independent experts, and look at the photos yourself.  Look. LOOK! LOOK AT THE PHOTOS!

Sorry I went all caps-lock on you.

Not only can the photos be used to assess the speed, that is one of the benefits claimed by your accommodating contractor, Optotraffic. In case you have yet to read their brochure, I quote from it again for your benefit.
While the primary evidence for issuing a speeding citation is the calibrated lane sensor, the two photos provide secondary evidence of speeding ...
See?

Now back to your report.
The Town’s officer in charge of the program has re-reviewed many of the tickets issued and has noted that many of the vehicles have applied their brakes by the time they have entered the picture zone. This is one reason the pictures cannot be used to determine the speed of the vehicles.
If you look at the photos just presented, you will note that the brake lights on Will Foreman's trucks are not lit. You might also check with your independent review team to see if it is physically possible for a truck such as Will's to decelerate from 76 mph to 35 mph in 50 feet.

(I'll save you the trouble. It is not possible. It would require braking at 3g's. Maximum braking is around 0.7g's. Professionals and top-notch equipment can reach perhaps 1g. To reach 3g's or more, you have to hit something head on.)

Not only that, you can see whether the car was decelerating as it entered your kill zone, assuming the driver managed to see your "automated speed enforcer" at the last moment. This time, I'll quote from Sigma Space System's patent, referenced previously.
The acceleration/deceleration of a moving vehicle can be estimated by comparing the speed estimates for the front and the rear of the moving vehicle
See.

I think you should check these things out before suggesting that citizen Foreman is trying to deceive you, and the judge, and everyone else with his speeding ticket images. To suggest that citizen Foreman's analysis is incorrect because one of your fellow "town officials" saw some brake lights on some photos is a bit over the edge.
BRENTWOOD ISSUES:
Some citizens raised the fact that Brentwood had rebated all tickets issued between June 24th and July 13th. Many believed this was due to a problem with the Optotraffic equipment.

We have checked with the Chief of Police of Brentwood and there was an administrative issue with the handling of tickets by the Brentwood staff. This was not a systemic 
Oops. Another mistake. I'm pretty sure you didn't mean to end the sentence with the word "systemic" and no punctuation. That's okay, though. I have no doubt you will find typos and grammos and other such mistakes in this post. I understand.

You failed to mention, however, that the systemic problem in Brentwood was the approval of 3,500 citations by someone who was not authorized to approve the citations, by someone who was not even an employee of the city at the time, by someone who should have known better. That person was in fact Brentwood's unemployed ex police chief.
INDEPENDENT VERIFICATION:
In order to provide a completely independent verification of the Optotraffic unit’s calibration, Chief Webb has instituted a verification process where he has had officers drive cruisers through the equipment at set speeds. The speed of the vehicle is verified by both the car’s odometer and a hand held radar/laser gun. This process will be repeated at a regular basis. We have the results of the Chief’s first test and it verified that the hand held radar/laser speed gun is in sync with the laser being utilized by the photo enforcement program. The Town’s hand held radar/laser speed guns are calibrated annually in order to be valid in any court appearance, and were used to show the town’s speed cameras are accurate
And that's how you end your report? Without punctuation. My oh my. I'll just make this obvious comment, then I'll let you be. Having one of your employees check the system a couple times with his speedometer (not odometer, Jeez!) and his a radar gun is not an independent verification.

So that's it for now, Forest Heights town officials. Keep up the good work.