The smell of unburnt marijuana alone is not probable cause to search a warehouse in Massachusetts, unless other evidence points to illegal activity, the state’s Supreme Judicial Court wrote in a ruling Monday.

But the court said there was plenty of other evidence to support a 2017 search of a warehouse in Amherst, where police found an illegal marijuana growing operation.

The defendant in the case, Gregory W. Long, was arrested in October 2017 alongside several others in connection with an 11,000-square-foot warehouse in Amherst, where police say they found an illegal marijuana growing operation.

Long was charged with trafficking in more than 50 pounds of marijuana, but his lawyer said the evidence against him should be suppressed. They argued that the police couldn’t rule out the possibility “that the odor emanating from the windowless, 11,000-square-foot, cinder-block warehouse was the product of the legal marijuana use, possession, or cultivation,” the SJC decision said.

In Massachusetts, adults over the age of 21 can grow up to six plants in a private residence, and up to 12 plants in a residence where two or more adults live.