> It’s obvious that the police will want a device that produces more convictions, no point in disputing that.
Is that obvious? If this were as overwhelming an incentive as you say, we wouldn't have accurate breathalyzers for alcohol. But we do, and it's simple to see why. 1) Cops aren't the only customers; medical establishments, individuals, and workplaces also have a legitimate interest in measuring impairment. 2) Tech like this doesn't remain novel forever, it can be checked for accuracy, and if you made a device that exaggerated impairment your reputation would tank, your company name would become a political hot potato, and your sales would never materialize. 3) There is definitely a point in disputing the idea that cops are indiscriminate gangsters roaming the streets trying to lock up any citizen they don't like the look of. Police have their personal and institutional biases, but by and large, most are interested in tools that allow them to safely and fairly administrate the rule of law. Police don't have much career or institutional incentive to arrest someone for a DUI at a traffic stop or not—they just stop bad drivers and check. It's prosecutors who are trying to rack up conviction numbers as a matter of career advancement and political viability. But even that gets checked: their work will be subject to an adversarial legal system, at which point any evidence that the device doesn't work would come out in court and tank their conviction rate.
So... where do you see perverse incentives here, again?
Do we have accurate breathalyzers for alcohol? AFAIK, the manufacturers aggressively resist requirements to publish their source code or calibrations for testing. Also, AIUI, the devices require recalibration for accuracy, and it's not clear that police stations perform such maintenance.
No idea how rampant this is, every system will have flaws. But I question whether we can use the alcohol breathalyzer example without acknowledging there are significant unanswered questions w/r/t accuracy.
A friend of a friend works at a facility which calibrates + certifies police breathalysers and by his account below 0,015% BAC the result is garbage, so some countries choose to set the limit at 0,02% which is enough for the devices to indicate properly most of the time.
Only if you're allowed to test the devices in question, and the courts believe your experts over the manufacturers.
This doesn't prove my point, but manufacturers do aggressively fight against researchers identifying flaws in their products. Given the high stakes (+ the fact this isn't a security issue, really), it seems like a major smell to me.
There are reports out there of people convicted, who are blocked from examining the devices used as the primary piece of evidence against them.
Also, after years of effort to discredit breathalyzer results, convictions ARE being overturned regularly.
The National Highway Traffic Safety Administration report to Congress [0] seems pretty clear in terms of the art of the science and the impairment observed from national data.
I would avoid incarceration of anyone from a test like this without significant and clear data that there is an actual problem we need to resolve. There are plenty of well proven driving problems we could focus on correcting.
Is that obvious? If this were as overwhelming an incentive as you say, we wouldn't have accurate breathalyzers for alcohol. But we do, and it's simple to see why. 1) Cops aren't the only customers; medical establishments, individuals, and workplaces also have a legitimate interest in measuring impairment. 2) Tech like this doesn't remain novel forever, it can be checked for accuracy, and if you made a device that exaggerated impairment your reputation would tank, your company name would become a political hot potato, and your sales would never materialize. 3) There is definitely a point in disputing the idea that cops are indiscriminate gangsters roaming the streets trying to lock up any citizen they don't like the look of. Police have their personal and institutional biases, but by and large, most are interested in tools that allow them to safely and fairly administrate the rule of law. Police don't have much career or institutional incentive to arrest someone for a DUI at a traffic stop or not—they just stop bad drivers and check. It's prosecutors who are trying to rack up conviction numbers as a matter of career advancement and political viability. But even that gets checked: their work will be subject to an adversarial legal system, at which point any evidence that the device doesn't work would come out in court and tank their conviction rate.
So... where do you see perverse incentives here, again?