People Against Drink/Drug Driving

Your phone can tell when you're high: Data from accelerometer and GPS sensors can be used to predict with 90% accuracy if someone is stoned, study finds

• An algorithm based on sensors data combined with the time of day and day of the week was right nine out of ten times
• The most important features were sensors tracking movements, GPS location 
• Current marijuana tests have a three-day window and are difficult to administer in the field
• The algorithm could 'deliver a brief intervention when and where it might have the most impact to reduce cannabis-related harm' 

By DAN AVERY FOR DAILYMAIL.COM PUBLISHED: 30 September 2021

Sensors on a person's smartphone can be used to determine if they're high with uncanny precision, according to a new study out of Rutgers University

Researchers at the school's Institute for Health, Health Care Policy and Aging Research found that an algorithm that combined sensors tracking movements and GPS location with data on the time of day and day of the week had a 90 percent accuracy rate in determining if someone was stoned.

The algorithm could help law enforcement and health professionals more accurately predict if an individual is currently experiencing 'cannabis intoxication,' according to a release.

'We might be able to detect when a person might be experiencing cannabis intoxication and deliver a brief intervention when and where it might have the most impact to reduce cannabis-related harm,' said co-author Tammy Chung, director of the Institute's Center for Population Behavioral Health in the statement. 

Researchers have been able to create an algorithm that predicts whether a regular pot smoker is high with 90 percent accuracy. The system combines GPS and movement data from their smartphone with info on the time of day and day of the week

The study, published in the journal Drug and Alcohol Dependence, evaluated the feasibility of using smartphone sensor data to identify episodes of 'cannabis intoxication' — being noticeably high— in a non-lab environment.

Just based on the time of day and day of week, the algorithm had a 60 percent accuracy rate

Getting high has been linked to slower response times, which can impair driving and other focus-intensive activities.

Existing marijuana detection measures — like blood and urine tests — present logistical issues and would be too time-consuming to use as an intervention.

In addition, such tests can return positive results for up to three days after a subject has last used marijuana and would no longer be considered high.

As more states legalize marijuana, a smartphone app could be used to determine acute cannabis intoxication, rather than just general usage. 

The authors of the study, who include faculty from Stevens Institute of Technology, Stanford University, Carnegie Mellon University, University of Tokyo and the University of Washington say future research should investigate how algorithms like theirs would rate in classifying people who use weed less frequently.

Most current marijuana tests can return positive results for up to three days after a subject has last used pot. The algorithm could help 'detect when a person might be experiencing cannabis intoxication and deliver a brief intervention when and where it might have the most impact,' researchers say

For complete article

17^th September 2021

Belgium is looking into whether it can prohibit navigation apps such as Waze and Coyote from showing where alcohol and drug controls are set up, after France announced it would ban the practice from 1 November.

Drivers using navigation apps such as Waze or Coyote can, as soon as they notice a traffic jam, indicate via the app where exactly it is. The app then alerts other users so they can avoid the route.

However, this is also the case with police checks, which has raised some ethical questions, as it allows drivers who are under the influence to choose an alternative route.

The French government now wants to counter this practice and will require the apps to block certain messages and notifications for several hours. This will apply to alcohol and drugs checks, or when the police are looking for a fugitive, for example, but not to speed checks.

Federal Mobility Minister Georges Gilkinet is investigating whether a ban could also be introduced in Belgium and has ordered a study on this by the traffic institute Vias.

“Hopefully politicians will follow our recommendation and warnings like these will no longer be issued,” Vias spokesperson Stef Willems said on Flemish radio on Friday, adding that the institute has been in favour of such a ban for a long time.

“That is not only to do with road safety, but it is also about someone who is not insured, and so on,” Willems said. “If everyone starts continuously warning each other about such checks, then it is just those kinds of people who are going to get away.”

For complete story

Volume 50, Issue 6, June 2021

Delta-9-tetrahydrocannabinol (THC) impairs driving performance and can increase crash risk. These effects are more pronounced in people who use THC occasionally and can last for up to eight hours with oral THC products. There is no evidence that cannabidiol (CBD) impairs driving. Patients using THC-containing products should avoid driving and other safety-sensitive tasks (eg operating machinery), particularly during initiation of treatment and in the hours immediately following each dose. Patients may test positive for THC even if they do not feel impaired, and medical cannabis use does not currently exempt patients from mobile (roadside) drug testing and associated legal sanctions.

For complete article

Dalgarno Comment: The term ‘behaviourally tolerant’ when used in a clinical report about drug driving issues always raises a red flag.

The research affirms, not only what we instinctively know, but what decades of long fought for science has told us, that intoxicants impair motor and cognitive abilities. Increasing the potential of turning a vehicle into a weapon against public safety.

The fight to have BAC limits introduced was a long and difficult one, but such measures are instrumental in reducing road tolls and associated harms. The increasing push to normalize cannabis use and introduce it to the currents of trade, even if in ‘medicinal’ contexts, means an increasing incidence of people choosing to drive whilst ‘medicated’. We understand from long established research that airline pilots  (image below) even after one low dose THC ‘joint’ failed on many task matrices.

The notable concern in the report was the reference to users ‘perception’ of their ability to drive with THC in their system. When drug user self-assessment becomes to diagnostic indicator of ability we have a serious problem.

It may be a factor to consider, but when the following statement: ‘Behavioural Tolerance’ is added to the criteria for evaluation, we have regressed, not only in thinking, but in methodology.  It is like going back to the pre-RBT (Random Breath Testing) days of evaluating driving capacity whilst drunk. If one could ‘walk a straight line and stand on one leg’, then that individual was legally ‘capable’ of driving.  Although you may have a BAC of .10 (twice the legal limit), if you can ‘prove behavioural tolerance’, then you can keep driving.

Intoxication and impairment cannot be left to subjective self-assessment, and very strict limits/penalties set on substances we know to diminish capacity and agency.)

Australian cannabis laws are dishonest and need to change | The Canberra Times | Canberra, ACT

Gino Vumbaca recommends that Australia learn from New York’s recent legalization effort.  Actually, the opposite is true.  New York should learn from Australia.  New York legislators were intent on lowering the crime category for stoned driving from misdemeanor to petty offense.  Only an uprising by safety advocates prevented that disaster.

Sixteen states in the US have zero-tolerance laws for at least some forms of drugged driving, similar to Australia’s laws.  It’s the zero tolerance that Vumbaca and others such as Michael White rail against.  There is a significant difference in the implementation of those laws between the US and Australia: in the US, a driver must exhibit probable cause of behavioral impairment before a toxicology test can be ordered.  

Writers like Vumbaca and White confuse the public by implying that drug per se limits, whether they be zero or some finite number, are selected to define impairment.  They aren’t.  They are selected as a social and political policy to deter impaired driving.  That is why we see different alcohol per se limits in different countries, all based on the same scientific data.

These writers also fail to distinguish between THC’s acute impairment and chronic impairment.  It is certainly true that chronic marijuana users can have THC circulating in their blood long after their acute impairment subsides.  But we’ve also seen from Gruber and others that chronic users maintain a low level of chronic impairment long after acute impairment has subsided.

Any level of THC in blood may not prove acute impairment, but data still support use of zero tolerance for THC in drivers as a sound social and political policy.

This is why we advocate for Tandem DUI per se which requires not one, but two elements to prove a violation of an impaired driving law: evidence of behavioral impairment and any level of an impairing substance in the driver’s blood or oral fluid.

Ed Wood (Driving Under Influence of Drugs Victim Voices)

www.duidvictimvoices.org