The ACLU of Illinois and the American Civil Liberties Union, along with the National and Illinois Associations of Criminal Defense Lawyers, filed amicus briefs in the Seventh Circuit and the Illinois Supreme Court in September 2023 urging those courts to adopt a rule that the odor of cannabis/marijuana alone – without additional facts indicating that someone is committing a crime – should not be a legally sufficient basis for police to search a car without a warrant.

In Illinois, possession of personal amounts of cannabis is now legal in many circumstances.  Police should not be able to use the odor of a legal substance as the sole reason to stop or search drivers.  Cars could smell of cannabis for a number of innocent reasons that do not indicate that the driver is impaired or otherwise violating the law. 

When allowed to use reasons such as the odor of cannabis to detain and search drivers, police often use their discretion in ways that discriminate against drivers of color.  We argue that, as a policy matter, courts should adopt a rule discouraging vehicle searches, so as not to worsen the existing racial and ethnic disparities among people police officers stop, search and charge with cannabis-related offenses. 

Data shows that police in Illinois are about nine times more likely to charge Black people with cannabis offenses than white people, despite the fact that cannabis usage rates are fairly equal between white and non-white individuals.  Police are also more likely to initiate pretextual traffic stops of Black and Latinx drivers overall, and to search those drivers after they are stopped. These pretextual traffic stops are statistically unlikely to turn up contraband – such as drugs – but they are profoundly harmful to Black and Latinx drivers and communities. 

If courts adopt a rule that the odor of cannabis does not provide probable cause for a vehicle search, it is unlikely to decrease community safety, but it is very likely to increase trust in the police and decrease racial profiling in vehicle stops and searches.

Pro Bono Law Firm(s)

Alexandra Block (ACLU-IL), Jonathan M. Brayman (Breen & Pugh), Clifford Berlow (Jenner and Block), Julian Clark (ACLU)