Those are the reasons why Chicago police said they had probable cause to pull him over. But Williams' subsequent arrest for "resisting arrest" and the interactions the officers had with onlookers is the subject of a more serious discussion about police use of force and harassment of the African American community under a police state.
Williams stopped to fill up his gas tank but ended up face down on the ground in handcuffs. While, arguably, no laws were supposedly broken, Williams claimed he was racially profiled so officers could search his vehicle for guns or drugs.
From the body camera footage worn by one of the officers, it appears Williams was in a state of shock when he was confronted by Chicago police at the Southend gas station. "Are you serious?" he kept repeating, all the while cooperating with police.