The 25-year-old Behanan was arrested Saturday night with three other men following a traffic stop.
Louisville police spokesman Dwight Mitchell says officers smelled marijuana in the vehicle and noticed drug residue on Behanan's lap in the back seat. Mitchell says a stolen AK-47-style rifle was found next to him.
Behanan is jailed pending an arraignment scheduled for Monday.
The 6-foot-6, 220-pound forward was a key player in Louisville's title run. Then-Cardinals coach Rick Pitino dismissed Behanan from the team the next season for a violation of team rules.
The NCAA vacated the championship in February as part of sanctions resulting from a sex scandal.
