HARRISBURG — The smell of marijuana can be a factor police use to justify a search without a warrant but can’t be the sole basis for it, the Pennsylvania Supreme Court ruled Wednesday.

The court said a state police search of a vehicle in Allentown three years ago was conducted only because the troopers smelled marijuana. A subsequent search lead to police confiscating a loaded handgun and a small amount of marijuana.

“The odor of marijuana alone does not amount to probable cause to conduct a warrantless search of the vehicle but, rather, may be considered as a factor in examining the totality of the circumstances,” wrote Chief Justice Max Baer for the majority.