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Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

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Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#251

Post by SannTek »

antisthenes wrote: post #71

> Even if the driver had smoked cannabis one minute before the traffic stop, the driver’s blood plasma THC level would have fallen 80%-90% in the first hour after ingestion, and even more so after two and a half hours. Can you source this claim from your front page? And if it is correct, how are you making sure the police correlate impairment with THC levels correctly? If someone smoked 2-3 hours before driving, woul…

Here is the source of the 80%-90% statistic: National Highway Traffic Safety Administration. Marijuana-Impaired Driving: A Report to Congress. July 2017.

The approximate window for cannabis impairment is 2-3 hours. Our sensor is currently calibrated to align with that window. The current threshold is around 10 pg/mL, although more trials are required to make sure that is the correct number.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#252

Post by davidw »

root_axis wrote: post #244
davidw wrote: post #240

Earlier quoted context omitted.

Given how dangerous automobiles are even for non-impaired people, I'd rather err on the side of caution, especially given that consuming is not something people need to do.

I prefer to err on the side of data before it is mandated that people be tested for marijuana at traffic stops in the name of "caution".

Makes sense to follow similar protocols to alcohol:

https://www.oregonlive.com/politics/2015/07/marijuana_and_dr...

In other words, this isn't something that anyone who gets stopped goes through. You get tested if you're driving erratically.

Driving is a privilege. It's easy enough to avoid doing it while high.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#253

Post by verall »

Noah_SannTek wrote: post #74
slg wrote: post #64

Earlier quoted context omitted.

I'm sorry, but this is just not true. People are innocent until proven guilty. If there is no evidence, then they aren't convicted (EDIT: for the record, testimony is evidence). Adding an avenue to collect more evidence is going to cause more people to be convicted. Sure, you will probably get some people exonerated, but there is no question that you will get a larger number of people convicted. I am not going to wei…

Apologies, one thing I forgot to mention is that once reasonable suspicion is established, and an arrest happens, if you aren't blowing over 0.08 for alcohol, police will request a blood test. It's possible that for frequent users, THC will show up in these blood tests even though they haven't recently smoked. If an officer screens you on our device (which only has a 3 hour window of detection) and there is no THC, t…

(American viewpoint about this device being potentially used in America. Courts and policing is different in Canada, and so my feelings here aren't neccesarily how it would work out there)

In many (most?) states you can refuse the blood test, until they get a warrant, even though you cannot refuse the Breathalyzer. I believe this will be used as a tool to make arrests and generate probable cause which will then immediately be used to obtain a warrant and blood test, which will hold up in court much better than the Breathalyzer alone or nothing at all.

I'm sorry, but even if this product works perfect technically I see it harming more people than it helps. Throw in chance of false positives and likely hood it is used by biased individuals in a biased way (only some individuals are told to blow multiple times, etc) and I really believe this product deployed in America would have a negative impact on most people.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#254

Post by mohaine »

chadash wrote: post #31

I don't understand the negativity in many of the comments here. I'm all for legalization of marijuana, but I actually think that the inability to test for people driving high is a very reasonable argument against legalization. I generally feel that people should be able to make their own choices, but not if those choices involve driving a 3000 pound piece of metal down the highway while impaired. Yes, we need to be c…

Well, this simply doesn't matter. There are already tests for impairment that failing will land you a DUI regardless of your breathalyzer test levels.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#255

Post by SannTek »

woah wrote: post #4

Sounds like it’s well-intentioned, but I’m afraid that given the incentives of all parties involved here, and the complexity of the technology, there will be a lot of false positives. It’s obvious that the police will want a device that produces more convictions, no point in disputing that. I’m wondering if you can elaborate on what incentives your company has to produce accurate devices, against your customer’s unst…

You raise a good point. Interestingly, your comments run contrary to what a lot of law enforcement officers have said to us.

In general, the police are hyper vigilant about buying only devices that are independently validated to be very accurate. Every conversation we have had has eventually lead to "is it NHTSA approved?". The reason for this need for third party validation is that the police are incredibly court room sensitive. If there is any chance a defense attorney would be able to pull out a study showing low specificity or sensitivity for a device, the police will simply not buy it. Third party validation gives them that guarantee.

You are right that the police want more convictions (or less time consuming convictions), but the way they do that is by having very accurate devices that are defensible in court, not inaccurate devices that risk cases being thrown out. That is why making sure our device has low false positive is very important.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#256

Post by JoeAltmaier »

Lots of talk about the consequences of false positives.

I understand the market for these devices is partly law enforcement. But another commercial market is devices installed in cars for habitual offenders. For alcohol detectors, something like half a million are installed in cars in America right now.

They have false positives, sure. Users learn to avoid substances that will trigger a false positive, because they want to drive their car. Its a massive inconvenience, but instead of a jail term, they are back at work etc driving their car.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#257

Post by alex_young »

mitchellst wrote: post #26
woah wrote: post #4

Sounds like it’s well-intentioned, but I’m afraid that given the incentives of all parties involved here, and the complexity of the technology, there will be a lot of false positives. It’s obvious that the police will want a device that produces more convictions, no point in disputing that. I’m wondering if you can elaborate on what incentives your company has to produce accurate devices, against your customer’s unst…

> 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)…

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.

[0] https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/documents/81...

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#258

Post by fragmede »

ac29 wrote: post #132
edmundsauto wrote: post #106

Earlier quoted context omitted.

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 witho…

If breathalyzers were inaccurate, uncalibrated, or unmaintained it would be trivial to get any conviction relying on their measurements thrown out.

Mind you, that's not unprecedented. https://arstechnica.com/tech-policy/2009/05/buggy-breathalyz...

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#259

Post by chatmasta »

abstractbarista wrote: post #227

I think this is really cool. I always wondered though, the way we correlate numbers to driving ability seems sketchy. Some people take multiple large dabs of cannabis concentrate - and they're barely feeling it. This is because they basically do this all day every day. Someone like that would fail this test, despite their motor skills remaining near baseline. It's clearly different for alcohol, because it directly in…

It’s funny to imagine a cop pulling over a stoned driver and putting him behind the wheel of a racing simulator.

Re: Launch HN: SannTek (YC S19) – Breathalyzer for Cannabis

#260

Post by SannTek »

mikepurvis wrote: post #242
chadash wrote: post #31

I don't understand the negativity in many of the comments here. I'm all for legalization of marijuana, but I actually think that the inability to test for people driving high is a very reasonable argument against legalization. I generally feel that people should be able to make their own choices, but not if those choices involve driving a 3000 pound piece of metal down the highway while impaired. Yes, we need to be c…

I'm sure this varies by jurisdiction, but I really wish my local police department (in Waterloo region) were willing to put even the slightest effort toward general road safety. As a four season bike/eskate commuter who wears a gopro, I am yelled at, swerved at, I witness drivers running stop signs, exiting driveways without looking where they're going, making RTOR without looking where they are going, driving at peo…

Glad to see someone else from Waterloo in the comments! I'm not sure that what local police department serves your area, but the Waterloo Regional Police Service are actually really ahead of the curve when it comes to drug impaired driving. They have more drug recognition experts per capital than almost any other jurisdiction in Canada and if I am remembering correctly they are making it mandatory to train new recruits in the standard field sobriety tests.

They should still be listening to your complaints, however. Hope you have better luck in the future.

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