Thursday, April 28, 2011

Automating Wrongful Convictions: Laser Beams Gone Wild

In Part 1, I provided an overview of the judicial farce that is Maryland, at least the speed limit enforcement portion thereof. You should probably read that post first if this one is to make any sense to you. At the end of that post, I've added a link which will bring you right back here. I'll wait why you catch up.

[Waiting patiently.]

Welcome back. As I promised, I'm going to give you my assessment of why the fiendish automated speed enforcer is putting its icy grip on our innocent citizenry.

To better understand the workings of Optotraffic's DLS-10S Automated Speed Enforcer, I reviewed their patent. It is number 7616293, "System and Method for Traffic Monitoring, Speed Determination, Traffic Light Violation, Detection and Recording." (You can read any patent for free using Google Patents. It's even easy to remember the URL: www.google.com/patents.) You can read the 38 page patent yourself if you wish, or you can trust me. Perhaps you should read it yourself. I'll wait.

[Waiting patiently.]

Sure. Like you read it.  So let's take a look at it. Here's the top. Click to enlarge.


You can see the patent number and issue date at the upper right. At the lower left, you can see that the patent was filed on April 29, 2005.

This is interesting. I don't see the name Optotraffic anywhere in the image or anywhere in the patent. Instead I see the patent is assigned to Sigma Space Corporation of Maryland. Let's check their web site and see what they have to say for themselves.
Founded in 1998, Sigma is a qualified organization with three Divisions that provide:
  • Aerospace Hardware
  • Science and Engineering Services
  • Commercial Products
Our customers include NASA, NOAA, DoE, DoD, universities, and commercial customers in the aerospace industry. Our mission is to provide tailored and innovative science and technology solutions and products that further the success and goals of our customers.
Look at that! The Department of Defense is one of their customers. Given that, I suggest they be careful labeling their paperwork as CONFIDENTIAL unless it really is Confidential from a defense standpoint. You're not supposed to be slapping that on paperwork that's not actually Confidential. It causes people to treat it as if it's meaningless.

I see also that the folks at Sigma Space Systems are customer oriented. They want to provide "products that further the success and goals" of their customers. If, for example, your city has a goal of generating 38% of its revenue via speed traps and bogus speeding tickets, you should contact Sigma Space Corporation.

If, however, you simply want to reduce traffic accidents, then I'm afraid Sigma Space Systems has nothing to offer. It seems automated speed cameras have not reduced traffic accidents.

If you wish to slow people down using a proven technique, you might want to contact Traffic Logix, a "manufacturer and distributor of traffic calming solutions that bring safety to the streets that our children play on and that all of us live on." They make these:


If, though, your city wants to generate more revenue from speeding tickets next year than it generated from all sources in the current year, you should definitely contact Sigma. They will gladly tailor a product to further your goal. From the Optotraffic site we find:
Optotraffic is a division of Sigma Space Corporation, a leading provider of instrumentation systems to the aerospace industry. Founded in 1998, Sigma provides LIDAR and other space-related instrumentation to NASA and other government agencies.
Optotraffic uses space-proven LIDAR technology to provide clients with highly-accurate, low cost traffic monitoring and enforcement solutions.
Here's the process. You send your tax dollars to Washington. They keep some for themselves and send some to Sigma Space Systems. Sigma develops some cool LIDAR technology, such as tracking volcanic clouds or helping aircraft figure out their altitude to within a centimeter. Sigma then goes all Forbin Project on you.


They try to dominate you by building a super-intelligent system of sensors and computers that  monitor you wherever you go. That system automatically sucks money out of your pocket and sends it to yet another government agency that watches out for you. The city takes a slice and sends the rest to Sigma. Sigma gets your money coming and going, the government gets its slice coming and going, and you get ...

But I digress.

How the Stupid Thing Works

Here's the money shot from the patent. I've cleaned it up a bit to make it easier to follow.


My first observation is that it's a crappy sketch. The two beams are supposed to be parallel, for gosh sakes. Gimme a break. And they're not supposed to originate from the same spot. They're supposed to be offset by some known distance, like the eyes of a hammerhead shark, thus:


Except the sharks would have lasers connected to their eyes.


This image from the patent shows the beams more correctly aligned, as parallel.

See.

Sigma absolutely needs to know the correct distance if they are going to calculate a speed using their CONFIDENTIAL and PROPRIETARY equation:

Measured Speed = Distance/Time

Sigma can presume the distance is equal to the distance between the two laser beams iff (if and only if) the beams are parallel.  Doesn't anyone at Sigma read their own patents before submitting them? I know it's just  a stupid sketch error, but it makes me wonder if they might have overlooked something else, something that might cause them to record the speed as 76 mph when it's only 35.

But I digress.

Look again at the three-image sketch, the one where the car is in three different positions as it passes beneath the lasers (which should be parallel for Pete's sakes). In the first of the three images, the two laser beams are both bouncing off the road.

The beams are being fired 10,000 times every second, so the time between any two sets of laser beams is 0.0001 seconds. That's why the automated speed enforcer needs its own fossil-fuel powered engine. You fire lasers 10,000 times a second, you're going to be needing some dead dinosaurs to power your system. Those solar panels aren't going to cut it. (Don't tell Al Gore.)

But I digress.

In the second of the three images, beam 1 is bouncing off the car and beam 2 is still bouncing off the road. That causes the system to start counting its laser pulses.

In the third image, both beams are bouncing off the car. That causes the system to stop counting its laser pulses. Now it knows both time and distance. The distance traveled by the car is equal to the distance between the beams (if the beams are parallel), and the time it took the car to travel that distance is equal to the number of laser pulses times 0.0001 seconds.

If the beams are 35 miles apart and the time between the second and third images is one hour, then the computed speed is:

35 miles / 1 hour = 35 miles per hour

Your actual distance between beams may vary. Based on the Sigma's patent and some behind the scenes math, I think the beams are closer to 2.5 feet apart. That's 2.5/5280 = .000797 miles.  Let's assume the lasers fired 487 times between the first and third images. That's 0.0487 seconds. The speed was therefore

2.5 ft / 0.0487 seconds = 51.3 ft / sec = 35 mph

Possible Error #1:  Sluggish Beams

Between beam firings, the system has no idea where the car is. It's brain dead during that time. If the car is travelling at 35 mph (51.33 fps) and the pulses are 0.0001 seconds apart, the DLS-10S system could make a distance error of:

51.3 ft /sec * 0.0001 sec = .00513 ft

If their beams are separated by 2.5 feet, the percentage error is

0.00513 ft / 2.5 ft = 0.002 = 0.2%

Two tenths of one percent of 35 miles per hour is only 0.07 miles per hour.

Possible Error #2:  Fuzzy Beams

It's similar to the sluggish beams issue. If the beams are not nice and crisp, if they spread out on their way to and from their target, then the car could be anywhere inside a big laser blob. Fuzzy beams introduce distance errors, just as sluggish beams introduce distance errors.

The thing here is that Sigma Space Systems is really, really good at getting really, really crisp laser beams to fire really, really close together. It's what they do. If their laser beams are narrower than 0.2 mm (the largest number conceded in their patent), then the fuzzy beam distance error is 0.2 mm, aka 0.00656 feet. That's pretty close to the sluggish laser distance error of 0.00513 feet. Together, the two phenomenon could lead to an error of 0.16 miles per hour at 35 mph.

Because Sigma fires their beams so rapidly and so crisply, this sort of distance error is itsy bitsy, teeny weeny, and they know it. That's why they discuss it in their patent, though they exclude other possible errors. That's why they rely on it when advertising their product, and when showing calibration charts for any particular machine.

Possible Error #3:  Bendy Poles

This one is easy. The cameras are on top of a big bendy pole. If the wind is blowing the cameras toward you at 12 mph, and you're going the speed limit, you're going to get a ticket for speeding..

Do the cameras bend in the wind? You betcha. I quote from an email I got from Will Foreman himself.
The Today Show visited our store yesterday. They spent about 3.5 hours with us. It was great! The best part was watching them film the telescopic tower sway when there was a breeze, or when a heavy truck or bus passed by.
Hahahahahaha.

That's great. The fine folks at Sigma Space Systems blow laser pulse calculations up your backside but forget to consider the wind. You can search their brochure and their patent until you are blue in the face, but you are not going to find the letters w, i, n, and d joined together.

I think the guy who couldn't draw parallel beams might have been the same guy who coordinated their fault tree analysis. What a bunch of buffoons!

The wind can move the cameras in really complex fashion. The lasers can move parallel or perpendicular to the road. They can rotate as the pole twists at its natural frequency. Since Sigma claims it can accurately detect movement with its lasers, I suggest they place two fixed targets at the base of their DLS-10S Automated Speed Enforcer and fire two lasers downward. If wind is not a problem, the lasers will always be able to reflect off the targets. If the platform stability lasers are not able to stay on target, then they should throw the whole thing into the next trash truck to (allegedly) speed by.

Possible Error #4:  Overworked Lasers

I also received an email from Ron Ely, the editor of the Stop Big Brother Maryland web site. He proposed four different sources of error, though he conceded each was "wild speculation and untested."  I think he was actually on to something in two of his four wild speculations. He speculated, for example:
... the 32' pole the sensors are mounted on could sway or vibrate, possibly due to wind or a large passing vehicle, causing the beams to move while the vehicle is passing them.
As I just noted, I think this one is smack on. With regard to another speculation, however, I think he whiffed.
... the device might not work correctly during times of high load.  It might take a short amount of extra time to take the second measurement, amplifying the speed measurement.
Delaying the second measurement would actually decrease the measured speed, but that is incidental. The point is that firing crisp pulses rapidly in succession is what Sigma is really, really, really good at. They may not be able to draw parallel lines, and it may not occur to them that they have a bendy pole, but they can fire lasers with the best of 'em.

Possible Error #5: Variable Vehicles

I think Ron also missed the mark with a variable vehicle speculation, though not by as wide a margin.
... many of the vehicles showing these errors are trucks, pickups, or buses.  These vehicles have a very different "profile" than a passenger car.  If the device was never tested on vehicles with different profiles they might not be able to handle the case correctly.
As long as the two beams read the same point on the vehicle, it doesn't matter what point the beams read. The DLS-10S is actually designed to track both the front of the vehicle as it enters the kill zone AND the back of the vehicle as it leaves. Again from the patent, I show a three image sketch.


In this image, Sigma is showing how its system can calculate the car's speed by monitoring when the car left the system's field of view. The math and the demands on the system are essentially unchanged from the case where the car is entering the field of view.

If every car had a  laser reflector on its roof, then the system could use that as well. (Don't tell the feds.) It makes no difference where the lasers look as long as they both look at the same place. It makes no difference how the car is shaped as long as the lasers each detect the same point on the car, or truck, or bus, or mule team.

There is an interesting point here, I hope. Sigma claims in its patent that their system can determine the deceleration of the car, as well as its average speed, as it passes through the field of view. This will allow them to catch those scofflaws who hit the brakes once they see the cameras. I'm sure Sigma is right about that, assuming each speed is measured accurately. If they know the car's speed on entry and the car's speed on exit, they can calculate both an average speed and a deceleration. Even I could do that.

But the fine folks at Sigma don't really want you to know about that capability. Their current defense is that Will Smith's car (and all the others) might be going 35 mph in the photos, but they were going 76 mph when they passed beneath the lasers. Sigma just says that. They don't show you the entry and exit speeds and allow you to calculate the deceleration yourself. They just claim you were braking, so there.

Now you might say: "Look at the pictures. My brake lights aren't on." But they will say "You must have released the brake just before the photos were snapped."

Then you say "but no car can decelerate that fast." And they say "You can't read the photos that accurately because of perspective. Our cameras, on the other hand, are calibrated against GPS satellites. Our speeds are accurate to within a small fraction of 1 mph, and you have to be going more than 12 mph above the speed limit before we can give you a ticket. Did I mention we are calibrated against GPS satellites?"

And then you say "but your patent explains that your system can calculate acceleration by looking at the change in the car speed as it enters and leaves the field of view. Why don't you show us that?" And then they say ... "That's confidential and proprietary."

I'm confident Sigma fears showing both entry speeds and exit speeds. It would open up a gigantic can of rather large worms. Showing the times on the photos, for example, has already caused them big headaches. Will and StopBigGovernment MD and all the others are using those times to show the Optotraffic DLS-10S Automated Speed Enforcer is full of crap.

I guarantee you the speed camera manufacturers (not just Sigma) will try to stop displaying the times on the photos long before they ever start showing the both the entry and exit speeds.

Oops, looks like I'm right already.  Here the speeds are seemingly being rounded to whole seconds, making photographic speed assessments much more difficult.

Sigma and the other speed camera manufacturers need to suppress the evidence, not highlight it.

Possible Error #6:  Near Sighted Lasers

Let's consider Ron's fourth speculation.
... the two beams could simply strike different parts of the vehicle, for a variety of reasons.
I think this is possible. I find two system "features" in the patent that might be relevant. I discuss here admission that sensors don't know exactly where the road surface is. They only know where the road surface is within some error range they call E. I'm going to repeat a sketch to remind you of that.


See. In the lower left is the uncertainty E, and a note. "Below this height NO car detection." What I can't see is how E is set in the system, or adjusted, or calibrated, or forced to be the same between any two cameras. I see nothing to tell me how large or how small E might be. E is a mystery variable.

Let's just say that one laser is more near-sighted than the other. It has a bigger E. It is more likely to interpret something above the road as road rather than car. In fact let's say that the laser is so near-sighted that it sees a bumper and still thinks it's looking at the road, because it uses a big E.

By the time the near-sighted laser recognizes your car, your bumper is already part way to the second laser. If you bumper is 6 inches deep, it is only 24 inches from the next laser, assuming the two lasers are 30 inches apart. This will cause an overcalculation of your speed by a ratio of 30 to 24, aka by 125%.  If you are traveling 38 in a 35 zone, plan on getting a ticket for traveling 47.

It gets worse rapidly if the lasers are closer together. If they are only 1 foot apart, than even a 4 inch bumper could lead to an error ratio of 12 to 8, aka 150%. If you are traveling the speed limit, plan on getting a ticket for 52 mph!

Possible Error #7:  Lack of Depth Perception

This one really surprised me. It's a second reason why the beams may detect different points on a car. It's not because one laser is more near-sighted than the other; it's because one has poor depth perception compared to the other.

As it turns out, the lasers don't detect just on distance, as one might expect of a laser ranging system. Instead, ... well, heck .. I'll just let the patent speak for itself.
Using the recorded delay in conjunction with the signal strength, the presence/absence of a vehicle can be determined.

... A change in the signal strength is defined as either an increase or decrease of the recorded voltage. In most cases, the change corresponds to a decrease of the signal strength due to slight misalignment of the optical sensors. There are however exceptional cases where an increase of the signal's strength can be observed due to high reflectivity of a car's surface aided by reflecting / scattering alignment conditions.

... 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.
Holy fatal flaw, Batman! In most cases of a signal strength change, it is merely because of a "slight misalignment of the optical sensors." But sometimes, on rare occasion, the signal strength change might indicate the presence or absence of a car. In all cases, however, we will use the signal strength change to imply the presence or absence of a car.

The laser ranging system clearly has a depth perception 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 shined two lights at it from random distances, it would always think the 100 watt bulb was closer than the 60 watt bulb, because the detection system was made stupid by the new variable-signal-strength feature.

If the DLS-10S 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 them 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. As we have seen already, that's bad.

Bad, bad, bad.

Possible Error #8:  Cross-Eyed Lasers

You've been extremely patient, so this will be the last possible error that I discuss, and I will make it quick.
 
I cautioned in Part I of the series that you should never cross the beams, that bad things would happen. Let's put some numbers to that claim.

Let's assume the lasers are 24 inches apart from one another and 35 feet from the target zone. Let's assume also that the lasers are misaligned such that the beams converge at an angle of 1 degree. Let me do some back of the envelope trigonometry, and I'll be right back with you.

Okay, I'm done. Over a distance of 35 feet, the converging beams would narrow the actual target distance by 7.3 inches, from 24 inches to 16.67 inches. That would cause the calculated speed to be overstated by a factor of 24 over 16.67, aka 1.44.

If you were traveling 35 in a 35 zone, you would get a ticket for traveling 50 miles per hour. I'm sure if you went to court and told the judge "I think the beams may have crossed," he would find in your favor.

So, is it possible the lasers could be misaligned by a degree. Well, let's read the brochure.
Each lane sensor is third party calibrated annually (by Maryland law) to verify the beam distance.
There you go. If the beam distance (the actual spread at the target) needs checking, there must be some fashion to adjust the beams. You wouldn't design a system that couldn't be adjusted unless you were absolutely positive it would always pass the verification check; otherwise you would have to throw the thing in the trash. Any thing that can be adjusted can be misadjusted.

Sigma knows their beams can be misaligned. They said so, in their patent. I just quoted it to you. Here it is again.
In most cases, the change corresponds to a decrease of the signal strength due to slight misalignment of the optical sensors.
So where's the yearly calibration for these things? Is that information available to the public? If the beams are found to have been converging, will all the speeds be re-calculated and fines refunded as appropriate?

Summary

Finally. Whew!

Here's what I think. I suspect people are getting lots of tickets they don't deserve because automated speed systems in general, and Optotraffic's system in particular, suffer from crossed-eyes and/or bendy pole syndrome.


----

The series continues here.

Saturday, April 23, 2011

Automating Wrongful Convictions (with Demon Devices from Hell)


Given that we have 2.5 million of our fellow Americans behind bars, and given that 10% of them may be innocent of the crime for which they are serving time, I believe that some form of automation is necessary to identify those who might be innocent. My efforts to automate matters have so far been somewhat unsuccessful, non-productive, ineffectual, feeble.

The State, aka The Man, has been much more successful at automating and increasing convictions. A natural fallout of automating and increasing convictions is automating and increasing wrongful convictions. Consider the case of Will Foreman. The State has charged Will with 40 crimes. So far, Will has prevailed on the first 5 cases to be heard. That leaves only 35 more. I expect he will prevail on each of them.

When I write about specific cases or individuals, I usually write about someone wrongfully executed (such as Cameron Todd Willingham), or someone serving a life sentence for a crime he did not commit (such as Byron Case) or someone serving half a century for a crime that never happened (such as Michael Ledford). I typically do not write of someone who has received speeding tickets.

In fact, let me think here. Yup. I believe this is the very first time, ever, that I have written about wrongful speeding tickets. It won't be the last. This post will be the first of a short series discussing the implications of Will Foreman's speeding tickets.

I don't write of Will and his speeding tickets because he is an acquaintance of any sort. I've never met or  communicated with him in any fashion. I had never even heard of him before I read of his situation. Also, I don't write of him because he needs my help. He certainly does not. I write of him because his situation is a microcosm of our justice system not living up to its ideals. I write of him because I hope doing so will help you see the bigger picture, the more serious injustice, the wrongful incarceration of perhaps a quarter million of our own.

The Machine

To understand the injustice the State of Maryland is attempting to heap upon Will Foreman, you must first understand the automated speed camera used to wrongfully ensnare him. I therefore refer you to a brochure for the Optotraffic DLS-10S Automated Speed Enforcer. Though that brochure is marked CONFIDENTIAL and PROPRIETARY, it is available on Google Docs for all to view. From that brochure, I present this sketch of the demon device.


I provide also this description of how the demonic device works, at least in theory.
The DLS-10S implements a simple time-distance method for speed determination. A Lane Sensor that contains two optical sensors monitors each traffic lane. The sensors scan the road in the direction perpendicular to the line of traffic. When a vehicle is detected, both sensors acquire its unique profile and record the time when a sensor detected the object. Since the distance between the sensors is well known, the speed can be determined precisely as follows: 
Measured Speed = Distance/Time
where the "Distance" is the distance between the two laser beams that cross the lane and the "Time" is the time between the vehicle breaking each of the beans.
Now you can see why the document was marked both CONFIDENTIAL and PROPRIETARY. If that equation ever got out, no telling what might happen.

The machine has to perform three tasks very well. First, it has insure that the two beams pointing at any lane are parallel. (Under no circumstance should the beams be allowed to cross.)


Second, it has to measure time precisely. This it can do, to within millionths of a second.

Third, it must be able to precisely determine when a car has entered (and/or left) its field of view. This is the most difficult task. This is where the DLS-10S guesses. This is where it gets things wrong.

I'll leave further discussion of the machine's inner working for a following post.

The Photos

Not only does the DLS-10S estimate the speed of a car, it takes two digital photographs of the car as the car "speeds" away. The purpose of the pictures is to capture an image of the license plate so that the registered owner of the car can be ticketed. Only one photo would be sufficient most of the time, but two photos reduces the chance of having the plate blocked by another car.

If the objective of the automated system is to reduce the extent of speeding, the photos turn out not be necessary. The digital signs that simply inform you of your current speed turn out to be quite effective.


However, if the objective is to suck money from the pockets of scofflaws, then you need the photos. In the previously mentioned brochure, the fine folks at Optotraffic provide two example photos. I show them below.



Each photo displays the location, date, posted speed limit, and measured speed of the car. In this case, the posted speed limit was 30 miles per hour and the measured speed was 42 miles per hour. You are looking at a traffic scofflaw. You are looking at a speeder.

(It's perhaps only coincidental that the car is declared to be traveling 12 mph above the speed limit. Maryland law requires a 12 mph threshold before an automated ticket can be issued.)

Each photo also shows the time the photo was taken, measured to thousandths of a second. The second photo even does some math for you. It subtracts the two times and displays the difference. In this case it is 0.406 seconds.

Taking a lead from Will Foreman, I overlaid the two pictures. (I used Gimp to create the overlays. If any of you want to use or learn Photoshop but can't afford it, Gimp is a free and excellent alternative.)


Pretty cool idea. What you see is two images of the same car allegedly traveling at 42 mph. The two images are separated by approximately one car length. That means the car traveled approximately two car lengths in 0.406 seconds. Approximately is the key word here. It's extremely difficult to determine distances accurately from a photo such as the one above, due to perspective issues. Note how small the car appears to be in the front image compared to the rear image. Perspective views distort dimensions in complex fashion.

The Case of Will Foreman

Will Foreman is the owner of Eastover Auto Supply in Oxon Hill, Maryland. If you know where to look on his web site, you can get a coupon for $5 off any purchase of $50 or more. Heck, you don't need to go  to his web site. I'll post the coupon here. Click to enlarge and see it in all its wonder.


Note that the coupon expired last century. Maybe he will honor it anyway. If you happen to drop into his store, tell him I said "Hi."

Eastover has multiple company vehicles. Eastover's employees drive those vehicles as part of their job. Eastover's employees suddenly started getting lots of traffic tickets for speeding through the city of Forest Heights. As owner of the vehicles, Will was on the hook to pay those tickets. That didn't make him very happy. He threatened to pass the cost of the tickets along to his employees.

That didn't make Will's employees very happy. They claimed they weren't speeding. They claimed they had learned where the traps were. They claimed that even though they conscientiously observed the speed limit knowing of the speed traps, they were still being ticketed. After a while, the employees began skirting Forest Heights altogether. They thereby added unnecessary miles to their trips, burned more fuel than necessary, burdened their employer with higher fuel costs, and pumped even more life-threatening carbon dioxide into the atmosphere. (Al Gore should be all over this once he reads my post. If you relay it to him, send him this one as well. And tell him I said "Hi.")

By the time Will's employees had given up even driving down what had become known as the Forest Heights Toll Road, they had racked up 40 tickets. At $40 per ticket, Will was staring at $1600 in fines. Somewhere along the line, however, Will had a flash of brilliance. He decided to overlay the two photos that came with each of his tickets. Here's one result, from the Stop Big Brother Maryland web site. (Those guys are all over the situation. Big time.)


The photo displays a posted speed limit of 35 mph and a measured speed limit of 56 mph. In my assessment, that's a bunch of crap. Will provides a somewhat more analytic assessment.
The length of this pickup is about 16 feet., meaning the truck should have traveled 1.82 truck-lengths (or 1 length + another 13.18 feet) to move at this speed.  IT IS NOT EVEN CLOSE TO THAT DISTANCE.  We've added guidelines to compare the image, showing that the distance is 1 length + the gap between the front and back of the two truck images.  That gap is much less than half a truck-length. We estimate this to be less than 4 feet based on the size of the wheel-wells.  That would work out to a total distance of less than 20 feet, which given the interval of 0.363s would be just under 38mph.  This indicates an error of 18mph, and speed 9mph below the threshold for issuing speed camera tickets under state law (47mph in this case).
You don't need to work through the math to see that the truck was not traveling anywhere near 56 miles per hour. Look again at the my composite photo in the Optotraffic example. There the car is allegedly traveling only 42 miles per hour, and look how far apart those images are separated. By comparison, the Eastover Auto Supply truck images are barely separated. By comparison, the Eastover truck is traveling much closer to the 35 mph limit, just as Will calculated.

Let's look at a second, even more egregious ticket.


Once again the time difference between the two photos is 0.363 seconds, and once again Will's trucks are just barely separated. Once again, it seems as if his trucks are travelling very near 35 mph. (It's hard to assess the speed much more accurately than that, given the perspective of the photos.)

In this case, however, the spawn-of-the-devil machine claims Will's truck was traveling at 76 mph. (Insert 5 exclamation marks here.)

The Trial(s)

Most people don't fight their tickets. Most people simply swear up a storm and pay the $40 ticket by mail.  Only a few go to court, appear before a judge (no jury trial allowed), and mount a defense. Even fewer prevail. Will was an exception.

I quote now from the article that first brought his case to my attention.
Five times and counting before three different judges, the Prince George’s County business owner has used a computer and a calculation to cast reasonable doubt on the reliability of the soulless traffic enforcers.
After a judge threw out two of his tickets Wednesday, Mr. Foreman said he is confident he has exposed systemic inaccuracies in the systems that generate millions of dollars a year for town, city and county governments.
He wasn’t the only one to employ the defense Wednesday. Two other men were found not guilty of speeding offenses before a Hyattsville District judge during the same court session using the same technique.
“You’ve produced an elegant defense and I’m sufficiently doubtful,” Judge Mark T. O’Brien said to William Adams, after hearing evidence that his Subaru was traveling below the 35-mph limit - and not 50 mph as the ticket indicated. ...
While Judge O’Brien let Mr. Foreman off the hook, he ruled against several other accused speeders who based their not-guilty pleas largely on gut feelings that the cameras were flawed, while reducing the fines for some who pleaded guilty.
And there you have it. The last paragraph sadly epitomizes the state of our judicial system. Those who plead guilty are treated more favorably than those who have the temerity to defend themselves. Everyone is presumed guilty, and only those who can mount a stout defense have any hope of a favorable verdict. The state is not required to prove anything beyond a reasonable doubt. Even the flimsiest of evidence is sufficient to sustain a guilty verdict.

Even though the judge had just learned that the Optotraffic DLS-10S Automated Speed Enforcer frequently provided false evidence for the state, the judge took the word of the machine over the word of a defendant. The judge merely presumed the machine was right, and merely presumed the defendant was guilty.

In doing so, he suborned perjury, by a machine no less. I guess he decided such subornation was necessary for the rapid administration of justice. If a few people were wrongfully convicted along the way, if a few pleaded guilty to avoid even harsher sentences, then so be it. You can't make a judicial omlette without breaking a few heads.

***
The series continues here.

Saturday, April 16, 2011

Mythbusters Exonerate Cameron Todd Willingham

While the Texas Forensic Science Commission fiddled, after having first been neutered by Governor Rick Perry, Mythbusters unintentionally demonstrated how fire spreads rapidly through a room, even in the absence of accelerants.

Imagine that! It's as if Dr. Gerald Hurst (our nation's foremost fire investigator) knew of what he spoke when he advised Perry to stay the execution of Cameron Todd Willingham.

For the geekly disadvantaged among you, Mythbusters is a cable television show in which Adam Savage and Jamie Hyneman apply the scientific method (loosely) to test the validity of rumors, myths, movie scenes, and adages. (I borrowed that description from Wikipedia. That's why it was so tantalizing.)

One of my favorite shows was their testing of claims that water heaters can explode so violently that they launch themselves through the roof. As it turns out, that can happen, and in spectacular fashion. To demonstrate, they constructed a small house, subverted the safety devices on the heater, and encouraged it to overheat. The results were astounding. Play the short link below to get just a nibble of what the Mythbusters are all about.


For those of you unwilling to part with 32 seconds to watch the video, I provide the money shot below.


Another favorite was when they tested a claim that two tractor trailers completely flattened a compact car unfortunately caught between them when the two trucks had a head-on collision. According to the claim, the compact car was not just flattened, it was fused to the trucks. This claim was busted, proven to be not possible. The car was certainly damaged during the recreation, but there was no fusing of metal.

However, and there is frequently a "however" on Mythbusters, Adam and Jamie decided to see if it would be possible to fuse a compact car between two trucks travelling at 700 miles per hour rather than a mere 50 miles per hour. To do that ... well, you should watch and behold.


For those of you unwilling to part with 4 minutes and 9 seconds to watch the video, I provide below a less impressive composite image of the car being flattened.


Though the car was clearly flattened, the 1 inch thick metal plate moving at 700 mph did not fuse with the metal on the car. They declared the myth busted.

Now, as much as I like many of the Mythbusters' segments, the show is starting to deteriorate. It's becoming too formulaic, the spontaneous banter is now scripted and poorly delivered, and the lure of product placement has caused them to show some real stinkers. The show dedicated to The Green Lantern movie was painful to behold, as I suspect was the movie itself.

Last week, Adam and Jamie investigated a scene from The Bourne Supremacy. It was during their recreation of a scene from that movie where they unintentionally and unknowingly showed how the Willingham fire spread rapidly and left behind evidence misinterpreted as use of accelerants.

In the movie, Jason Bourne gets out of yet another tight spot (imagine that) by creating a MacGyver-like explosion in a room. He turned on the gas, put a magazine (the kind you read) into the toaster, and left. The magazine caught fire within 25 seconds and ignited the gas just as Bourne's pursuers were about to enter the room. The pursuers were thrown head over heels backwards by a giant fireball, and Jason Bourne escaped.

Adam and Jamie began their investigation by placing a magazine in a toaster and recording how long it took too ignite. It took 12 minutes and 2 seconds to ignite. (They reveal online that they had to defeat a safety mechanism on the toaster to keep it from automatically tuning off due to overheating.)

They next tested a series of magazines and newspapers to determine if any such printed material would ignite within 25 seconds. None of them did. The newspaper ignited most quickly, in 1 minute and 40 seconds.

They then constructed a small plexiglass enclosure to determine the range of fuel-air mixtures in which natural gas (mostly methane) will ignite. They knew the answer beforehand (around 9% gas for optimum explosion) but they wanted to demonstrate. The point is that if there is only a little gas in the room, the room will not explode. Similarly, if there is only a little oxygen in the room (because there is too much gas), the room will not explode.

Having completed their preparatory work, they built a full size room, and pumped methane into it as a magazine belatedly caught fire in a toaster. Nothing happened.

During the second test, they decided to pump more gas into the room, mix it better, and subject it to a more reliable ignition source. The removed the toaster from the table, covered the table with bricks, and placed an artificial fireplace log on the bricks. The bricks were there, obviously, to keep the table from being ignited by the fireplace log. Adam and Jamie obviously did not know what awaited them.

Hang on. After all this writing (or in your case, reading), here we go.

Scene 1:


Adam Savage lights the artificial fireplace log on the brick covered table, then makes a quick exit.

Scene 2:


The fireplace logs performs pretty much as expected.

Scene 3:


Since there is no chimney for the heat to escape, the heat accumulates above the table. Within four minutes of lighting the log, the ceiling catches fire.

Scene 4:


Some burning material drops from the ceiling and sets one of the chairs on fire.

Scene 5:


 The fire begins to spread across the ceiling.

Scene 6:


The couch begins to smoke. It's near ignition, not because anything is falling on it, but because of all the radiant heat from the ceiling. When it ignites, it will not ignite in any particular region. It will ignite all at once.

Scene 7:


The magazines ignite just before the couch. Nothing fell on them to make them ignite. The heat radiating from the ceiling is sufficiently intense to ignite the magazines from afar. A human would catch fire just as easily. Those who say Willingham must be guilty because he did not go back and save his children have no idea what they are talking about. A human could not bear the heat. Even if he magically could, he would simply combust and ignite.

Scene 8:


The couch and the bookshelf ignite simultaneously. You are looking at the onset of flashover. The fire radiates so much heat that most everything in the room ignites at once. It happens so fast, it seems as if the room explodes.

Scene 9:


Just moments later the floor ignites. Look at the pattern being burned into the floor. Texas would confuse those patterns with evidence of accelerant being poured on the floor. Because of their confusion, yet another innocent man was given the needle.

Scene 10:


The fire races across the ceiling and floor, leaving more faux evidence of accelerants.

Scene 11:


The rapid increase in heat and gas generation causes the walls to fail and the fire to vent. The Mythbusters' demonstration room was built nowhere near code, and quickly failed at a corner. More typically, the framing withstands the forces better than the windows. More typically, the windows blow out.

Also, the ceiling is beginning to burn through. The Mythbusters used plywood, not wallboard, for the walls and ceiling. Though the paper on the wallboard is flammable, the gypsum inside the wallboard provides a good fire barrier. In an actual house, the ceiling would not have burned through so quickly.

Scene 12:


Back inside, the room is growing darker. Left unchecked, it will soon become impossible to see in the room. Had there been a larger fuel load in the room, the smoke generation would have been more rapid. In the Willingham fire, which took place in the children's room, the fire thrived on a bed, two cribs, a dresser, curtains, a rug, a Little Tykes Oven, and a child's large plastic slide.

The fire consumes the floor. In the Willingham trial, the experts said that couldn't happen unless an accelerant was first poured on the floor. Their logic, the logic that the Texas Forensic Science Commission refuses to fault, was that "fire burns upwards."

The images show how a fire can spread so quickly. They help you to understand how people in one room can be killed while people in another might escape, and why rescue efforts by untrained, unequipped loved ones are bound to fail. They do not help explain how the Willingham fire started. It clearly did not start by someone placing an artificial fireplace log on a brick covered table.

If you are interested in learning more about the actual cause of the Willingham, there is only one book available. It is my work Inferno, available at Smashwords for a mere $0.99. I present below the introduction to that august work.
Amber was once again drawn to the heater, to its bright flickering flame, to its warmth, to its forbidden mysteries and charms. Both Mommy and Daddy had caught her before, putting things too close to it. Daddy had even given her whuppings, but he was asleep in the other room, and Mommy was not even home. 
Perhaps she wanted to move some of the fire from the heater to her Little Tykes oven sitting nearby. Perhaps she simply wanted to put something inside the heater and watch it disappear. 
Maybe a piece of drawing paper. Maybe one of her socks, the one she wasn't wearing when she was pulled barely alive from the house. Maybe it was the sock that was never found. 
Whatever it was, when it burned it was scarier than the fire in the heater. It burned closer and closer to her finger and her thumb as she held it at arm's length. But it was so hot. It was the hottest, scariest thing she felt, ever, so she flung it away, and then the curtain was on fire. The curtain between the heater and her little oven was on fire. She was going to get in trouble again. She was going to get another whupping. 
Fear of anger and whuppings, though, were quickly overcome by horror. The fire was growing larger and larger and scarier and scarier. She retreated as the fire climbed the wall to the ceiling. The smoke got inside her and made her cough. She could feel the heat on her skin, on her face and neck and shoulders. She had to get away, but the gate was there, blocking the doorway, keeping her from the safety of her Daddy's arms. 
Her sisters too were scared. They were crawling away as fast as they could, crawling towards the far corner of the room. One of them made it underneath the crib. 
Now the top of the room was on fire, and it was getting dark even though it was just morning outside. She couldn't breath and face burned, and her neck and her bare shoulders, and she wasn't even close to the fire. She didn't want to keep it a secret any more. She wanted her Daddy to save her. She screamed and screamed but he didn't come.
So she did what her sisters could not do. She climbed the child gate and ran to her Daddy's room, screaming for him. 
"Daddy, Daddy!" 
She couldn't see him because the smoke was there too, in his room. It was everywhere. She could hear him though. He was yelling at her to run, to go outside. But the fire was there where he wanted her to run, and she wanted him to save her. She climbed into his bed, but he wasn't there. 
Instead of him saving her, she would save him. She would save him with her screams and her pleas, by awakening him, by telling him of the fire, by taking his place in the bed, by breathing in the smoke that would have filled his lungs instead of hers. 
It wasn't heroism that caused Amber to take her Daddy's place. A two-year-old cannot be heroic. She can only be afraid of fire and smoke and dark. She can only be expected to seek the safety of Mommy or Daddy. Amber did everything a two-year-old could and should do. She screamed, she climbed the gate, and she ran for help. In doing so, she bought a reprieve for her father. 
The fire, however, would not be denied. Disguised first as justice and then as a needle, it would eventually consume her father just as surely as it had consumed her sisters, just as surely as it consumed her.
If, instead, you would like to understand how a jury can send an innocent man to death row, consider The Skeptical Juror and The Trial of Cameron Todd Willingham, on Kindle for only $2.99 or in the old-fashioned print format for $19.17.

Monday, April 11, 2011

The Impending Execution of the Repulsive Clarence Carter

Clarence Carter is waiting on Ohio's death row waiting to be executed on 12 April 2011 for the murder of Johnny Allen (no relation). There is no dispute that Carter beat, kick, and stomped fellow inmate Allen to death. Carter claims self defense.

From the clemency hearing for Clarence Carter, I offer the lurid details with my comments in italics.
In December 1988, Clarence Carter, defendant-appellant, and Johnny Allen were inmates in Range "E" at the Jail Annex to the Hamilton County Courthouse. Allen was being held on a theft offense. Carter had been found guilty of aggravated murder on December 9, 1988, and was awaiting sentencing. On December 28, Carter struck and kicked Allen numerous times over a twenty to twenty-five minute period, necessitating Allen's hospitalization. On January 5, 1989, Carter was sentenced to life imprisonment for the prior aggravated murder. On January 11, 1989, Allen died as a result of Carter's assault.
[So let's see. Nineteen days after being convicted of murder, while still in jail, Carter beats, kicks, and stomps Johnny Allen to death. I presume he had a good reason rather than simply a bad temper.]
Inmate Joseph Carroll testified that he and Allen were watching television on a mid-December evening when Carter came in and switched channels. Allen said to Carter, "Don't we vote on this?" Without saying anything, Carter punched Allen in the eye, then resumed watching television. Allen left to clean up the blood flowing from a cut above his eyebrow. Inmates Calvin Johnson and Phillip Brewer confirm that Allen and Carter exchanged words, and that Carter struck Allen. However, Johnson and Brewer assert that Carter was watching TV, and Allen changed the channel. Allen did not report this incident to jail authorities.
[Okay. It was over a TV incident. Allen's supporters argue with Carter's supporters over who violated the TV rules, but everyone agrees that Carter punch Allen in the eye.]
Carroll further testified that about a week before December 28, Carter found a broken metal spoon handle in a hole in the shower ceiling. After a brief discussion with Brewer, Carter returned the handle to its hiding place.
On December 28, after lunch, Johnson saw Carter retrieve the metal handle from the shower ceiling. Johnson asked Carter what he was going to do. Carter did not reply. About ten minutes later, around 1:10 p.m., the confrontation which led to Allen's death began in "E" range, a common area into which approximately twelve cells open.

According to Carroll, Allen was in his cell when Carter told him it was his tum to sweep the floor. As Allen walked past Carter to get a broom, Carter "jumped on him, punched him, [and] knocked him down." As Allen lay on the floor, Carter "leaned over him, punched him, kicked him and choked him."
[I guess I hadn't mentioned previously that Carter also choked Allen. I suspect though that Carter just reacted to an ugly situation, that there was no premeditation involved. I'll bet as soon as Carter got just a moment to compose himself and think about his actions, he would realize that he should use his words, not his fists and feet.]
Several times during the assault Carter stopped and walked away before returning to the attack.
[Oops.]
Twice he used a mop to wipe blood off his tennis shoes.
[Double oops.]
During the assault Carroll said to Carter, "[d]amn C.C., you don't like him, do you." Carter replied "no," and went "back down to where Johnny Allen was, punched him, kicked him some more, stomped on him."
[He's making it somewhat more difficult to suggest there was no pre-meditation.]
After the second beating, Allen managed to get up and sit on a bench, but Carter came back, knocked him off the bench, and continued to kick and choke Allen. Allen never threw a punch or provoked Carter.
[I'm starting to think that maybe Carter did have time to meditate in between beatings, and stompings, and kickings, and chokings.]
Inmate Calvin Steele described Carter's initial blow to Allen as a "sucker punch," delivered suddenly and without warning. Carter struck Allen ten or fifteen times. Allen never struck or attempted to strike a blow at Carter. At one point, Carter returned to his cell and stuck his own leg with some kind of object; he then came back and stomped on Allen's head with his foot. Carter's assault on Allen lasted twenty or twenty-five minutes. When Steele asked Carter to stop, Carter told Steele to "[g]et my ass back downstairs." (Steele was standing outside the range in the "bull run," the guard's access way.)
Richard Cunningham saw Carter hit Allen four or five times, then choke Allen, who lay on the floor. As he was beating Allen, Carter said, "[t]hat m ..... f.... tried to stab me." Carter seemed to be in a rage, but appeared to know what he was doing.
[I think when they typed "m....f...." they meant "motherfucker." Why do we, as a society, get the vapors when faced with a vulgar quotation, but have no compunction about sticking a needle in someone's arm and pushing lethal drugs?]
Cunningham testified that "Carter started kicking him [Allen] down the range by his head, and by his ribs, and he was pulling his head in my bars and stomping his head like a pop can on the floor. And his head was bouncing up off the floor. Blood was everywhere. Guys was on the range saying: Come on, CC, you are going to kill the man. Quit. Leave him alone. Carter wouldn't let up. He kept on doing it and doing it, he wouldn't quit."

Carter claimed that Allen assaulted him with the shank and that he, Carter, merely defended himself, being carried away with rage. According to inmate Robert Chapman, a defense witness, the fight began when Allen, holding the metal spoon handle, began hitting Carter. However, Chapman acknowledged that he previously told investigators he was asleep. Howard "Tub" Bums, a high school friend of Carter, heard Carter yell, "Tub, get the police."

Brewer said he saw Carter and Allen arguing on December 28, and Allen was holding some kind of metal object in his hand. After a few seconds, Brewer returned to his cell. He explained, "[i]n a place like that you mind your own business, and that's what I was doing."

Around 1:30 p.m., sheriffs deputies heard unusual noises, like an object being banged against steel bars, and went to investigate.
[Nice work on the deputies' part. The fight had been going on for twenty minutes before the guards even heard anything. That object they finally heard being banged against steel bars was apparently Allen's pulpy head. The State incarcerated him for theft. They had a responsibility to protect him. The penalty was supposed to be time behind bars, not oblivion beneath six feet of dirt. That sucks.]
When they arrived at "E" range, they found Allen lying face down on the floor, in a pool of blood. Deputy Raymond J. Loebker saw Carter drop the shank. Loebker described Carter as sweating, breathing heavily, but without any visible signs of injury. Sheriffs Lieutenant John Douglas saw the metal handle on the floor, four feet from Allen, and retrieved it for later examination.

[Several paragraphs from the clemency summary not included here.]
According to Doctor Harry J. Bonnell, Chief Deputy Coroner, Allen's heart and breathing stopped on January 10th, but doctors revived him. A January 11th examination revealed that Allen was brain dead. Doctors then disconnected life support systems.
[After everything I read prior to this, this next bit was the one that hit me hard.]
Dr. Bonnell performed an autopsy on January 12th. Allen was 5' 10", and weighed 122 lbs.
[Way to go, Ohio.]
Clarence Carter
Maybe Ohio should do away with the needle and simply trick death row inmates into changing the TV channel right in front of Clarence Carter.

Now on to my boilerplate.

I oppose the execution of people who might be factually innocent of the crime for which they are to die. I suspect that to prevent the execution of the factually innocent, we might have to ban the death penalty entirely.

I find no evidence that Clarence Carter did not punch, kick, stomp, and choke Johnny Allen to death. I find his claims of self-defense to be absurd. Since I limit my efforts to those people who may be in all respects factually innocent, I stand mute with regard to the execution of Clarence Carter.