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Following Cannabis Legalization, Does the Odor of Cannabis Provide a Police Office with Probable Cause to Search a Motor Vehicle?

"The Odor of Cannabis is an Aroma of Legality"

On January 10, 2024, Attorney James W. Mertes of the Law Firm of Mertes & Mertes, P.C. argued for the second time in just this session before the Illinois Supreme Court. As with all cases before the state's high court, the case is of major legal importance with far-reaching impacts. The issue now before the Court is whether the odor of cannabis provides a law enforcement officer with probable cause to search a motor vehicle following the legalization of marijuana.

"The possession of cannabis has been legalized in the State of Illinois. The odor of marijuana is an aroma of legality. The odor of cannabis emitting from a motor vehicle, standing alone, no longer provides a law enforcement officer with probable cause to believe that the vehicle contains evidence of a crime. Rather, the odor of cannabis now represents but one factor in a probable cause determination."  


Mertes did not argue that law enforcement officers cannot consider the odor of marijuana as a factor in their probable cause determination. Rather, Mertes argued that the odor of cannabis cannot be the only factor in that analysis.

In response, the Government argued that the Illinois Vehicle Code requires that cannabis must be transported "in a sealed, odor-proof and child-resistant" container. The Government argued that if the odor of cannabis can be detected, then that is evidence enough that it is not being transported legally.

Mertes said, "even if this Court finds that transportation in an odor-proof container is a requirement of law, the odor of raw cannabis does not establish probable cause with which to believe that cannabis is being unlawfully transported."

 Mertes argued, "the Government’s cynical view of its citizens finds no countenance in our Constitutional protections. The Government argues that any odor of cannabis inside the passenger compartment of a motor vehicle must necessarily demonstrate its unlawful possession. Citing People v. Hill, the Government argues that police officers and trial courts should not consider innocent explanations for the conduct of their citizens. The Government affords no regard for the vast multitude of innocent ways in which the odor of the legal substance may exist inside a vehicle. Instead, the Government claims that if the odor of raw cannabis odor can be detected, then illegal possession of raw cannabis must be occurring. The Government advocates trespass upon a fundamental constitutional right by erring against, not in favor of, liberty."

The case is now under advisement before the Illinois Supreme Court. In other words, the high Court, comprised of seven justices, is now deliberating and writing its opinion. The Supreme Court's decision on this issue will determine the law that applies throughout the entire State of Illinois.

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