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 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.

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.