Sunday, January 9, 2011

Technical Glitch May Cause Errors in Some Cameras

A recently released report exposed a software defect in a certain model of LIDAR(laser) based speed camera which can cause errors, including potentially assigning violations to the wrong vehicle.

The issues was discovered by the recipient of a Maryland ‘SafeZones’ speed camera citation.  The recipient of the ticket stated that he specifically recalled the incident when he saw the camera and that his cruise control had been set to substantially lower than the speed shown on the citation, and that he recalled this was confirmed by both his GPS and the mobile speed trailer sign at that location as being far below the speed on the citation he received. 

The driver said he spent enormous amount of time researching the matter.   He obtained the annual calibration certificate, daily setup logs, and operating manual** from the SHA though a public information request, which showed that the speed camera was a VITRONIC Poliscan.
[**CENSORED!!!! VITRONIC has forced the site where the operating manual was being kept online to pull it under threat of legal action.  That manual describes various ways citation images can be "Not Valid As Evidence", possibly indicating errors. They do not want you to see this stuff or use it in your legal defense!!!]

One thing he noticed early on was that the calibration certificate was issued by VITRONIC.  This seemed inappropriate because Maryland law states that “(6) (i) A work zone speed control system shall undergo an annual calibration check performed by an independent calibration laboratory. “, and that the manufacture could hardly be described as “independent”.  We note that the SHA’s speed camera contractor mentions the Vitronic Poliscan in their sales material and states “IACP cannot test Scanning LIDAR”(International Association of Chiefs of Police).

The driver eventually discovered that the Poliscan devices had been the subject of accuracy questions in Germany where they are built and where they are commonly used.  The driver then discovered a study, released in December 2010 and performed by the Chamber of Commerce and Industry Lahn-Dill(Germany),  which revealed that a defect did in fact exist in certain versions of the software deployed on VITRONIC Poliscan sytems.

The full report, which you can read here, is written in German.  However we have created a (machine) translation of the text which you can read in English.

The problem results from the fact that the Poliscan speed camera does not take photos a fixed amount of time after speed measurements are taken.  Under certain circumstances, the delay can be long enough for the triggering vehicle to move a substantial distance, even entirely off the frame.  While normally this would simply result in no citation being issued.  But if you happened to be traveling in the same direction as a speeding vehicle, you are S.O.L. : “This is [at] first unproblematic, if there is nothing to evaluate. Differently however [is] the situation, if then nevertheless coincidentally another vehicle of the same driving direction is so unfavorably in the proximity that the protractor on the front of this vehicle is illustrated. Then erroneously the measured value is assigned to this vehicle.

The report noted that the Poliscan’s self tests would NOT detect whether such errors took place: “if with a PoliScanspeed - measuring instrument a camera function defect arises - this can remain unidentified despite equipment self-monitoring with devices with the software-Version 1.5.3”.  The lag between the speed measurement and the photos is not recorded on citation images, thus an innocent driver receiving such a citation would have no evidence to prove such an error occurred.  Worse yet would be if the speeding vehicle had moved all the way out of frame, there would be nothing to indicate to a citation approver that the violation was assigned to the wrong vehicle (and that assumes such reviews are not simply rubber stamps, an assumption which is highly questionable).

A software fix has been apparently been built to mitigate the problem, although it is unknown whether it completely eliminates it or how many machines have not yet been updated.  The calibration certificate for the SHA camera provided by our source showed that it was dated in May 2010, prior to the creation of the software fix. Thus even if the software fix had already been applied on this particular machine, the devices could not have been certified to be properly calibrated since the change.

The Safezones program had reported issued over 300,000 citations as of November 30, 2010.

The individual discovering this information was unable to present it in court due to the fact that his case was dismissed when the state failed to present the camera operator at the hearing and he had a certified mail receipt proving that he had sent a request for them to appear.  Presenting the actual operator upon request is something which other jurisdictions such as Montgomery County have recently tried to assert that they are not required to do, and which district courts have ruled differently on in different cases .  We had previously speculated that a government agency could choose not to present the physical operator if they did not wish for the operator to be forced to testify to certain facts.

Laser(LIDAR) based systems are preferred in some situations partially because they are supposedly capable of distinguishing between vehicles (marketing documents released by ACS specifically state that their radar systems cannot distinguish between vehicles in different lanes).  To some extent they are also selected because the technology ‘sounds more advanced’.  However this does not necessarily mean they are immune to technical problems.  For example, Chevy Chase Village started using laser based systems in 2009, provided by the same contractor (ACS) as the safezones program, and shortly afterwards the following was reported in the minutes of one Chevy Chase Village Meeting:  “Ms. Stephens asked why there was a depletion of the revenues after obtaining the new laser cameras. Ms. Davis-Cook stated that the cameras have not been performing as expected. She advised that Chief Gordon has recently been in contact with the camera vendor to fix the current technical problems with the camera. has placed a Public Information Act request with the SHA and asked for answers to questions regarding the versions of software on the machines and the history of software updates, among other things, but have not yet received a response.  We will have more on this as we get additional information.  Until then, you might want to treat this as a reminder that if you don’t think you were speeding you should not assume you are wrong and that a machine is always right.