Rapper's Associate Waved Around Constitution During Stop of Tour Bus

Cops eventually towed the bus to a police lot, got a search warrant, and arrested 2 Chainz and his entourage

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.