DETROIT — The odor of marijuana alone isn’t a sufficient reason for police to search a car without a warrant, the Michigan Supreme Court said Wednesday.

In a 5-1 opinion, the court threw out gun charges against a man whose car was searched in Detroit in 2020.

Voters in 2018 legalized the possession and use of small amounts of marijuana by people who are at least 21 years old, though it cannot be used inside a vehicle.

“The smell of marijuana might just as likely indicate that the person is in possession of a legal amount of marijuana, recently used marijuana legally, or was simply in the presence of someone else who used marijuana,” said Justice Megan Cavanagh, writing for the majority.

The smell “no longer constitutes probable cause sufficient to support a search for contraband,” Cavanagh wrote.

Two lower courts reached a similar conclusion.

In a dissent, Justice Brian Zahra said he favored returning the case to a Detroit-area court to determine whether any other evidence supported a search by police.