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

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."

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.

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.