The Druid App was developed by Professor Michael Milburn at UMass/Boston. DRUID allows cannabis users (or others who drink alcohol, use prescription drugs, etc.) to self-assess their own level of impairment and (hopefully) decide against driving if they are impaired.

California NORML is promoting DRUID on their website, and has been featured:
On NPR’s All Things Considered:

On television:
On Spokane Public Radio:

NORML Canada members are encouraged to download and use the app as a potential tool to minimizing the concerns about impaired driving once cannabis is legal, and today.




Cannabis Driving Studies 2017 to 2002 PDF




Crash Fatality Rates After RecreationalMarijuana Legalization in Washington and Colorado

Marijuana and Driving: A Review of the Scientific Evidence

Should Per Se Limits Be Imposed For Cannabis? Equating Cannabinoid Blood Concentrations with Actual Driver Impairment: Practical Limitations and Concerns

Cannabis and Driving: A Scientific and Rational Review

Marijuana and Psychomotor Impairment

Imposing Per Se Limits For Cannabis: Practical Limitations and Concerns

Study: Cannabis’ Influence On Driving Performance Differs Significantly From That Of Alcohol

Pot, Psychomotor Performance, and Public Policy

NHTSA Report: Evidence Fails To Support Proposed DUI Impairment Levels For Cannabis

Marijuana DUI Workgroup Recommendation to the Drug Policy Task Force and Colorado Commission on Criminal and Juvenile Justice

Presence Of THC Metabolite Alone Not Evidence Of Driver Impairment, Court Says

Study: Medical Marijuana Laws Associated With Fewer Traffic Fatalities

Marijuana Legalization and Effects on Highway Safety: US National Highway Traffic Safety Administration reports no statistically significant crash risk increase in marijuana‐positive drivers.

Massachusetts High Court: Field Sobriety Tests Are Not Valid Measures For Determining Marijuana-Induced Impairment

AAA: Per Se Thresholds For THC Are Not Scientific

Study: Per Se Driving Limits For THC Ill Advised

Psychomotor Impairing Effects Of Cannabis Are Nominal In Experienced Users, Study Says

Detection Of THC In Blood Not Necessarily Indicative Of Recent Pot Use, Study Says

Study: Elevated THC/Blood Levels Persist In Habitual Consumers