You'll recall, cops pulled over 2 Chainz' bus because of a busted taillight, but upon approaching the vehicle ... cops say they smelled pot and attempted to search the bus.
But the driver refused to let cops on board -- and according to the police affidavit which was just released, one of the bus' passengers actually held a physical copy of the U.S. Constitution against the bus window ... "as if challenging officers" with his civil rights.
Source: TMZ. Read full article. (link)