FERGUSON, MO - AUGUST 18:  Police lob tear gas at people walking near a protest over the killing of teenager Michael Brown on August 18, 2014 in Ferguson, Missouri. Police shot smoke and tear gas to disperse the protestors with as they became unruly.  Brown was shot and killed by a Ferguson police officer on August 9. Despite the Brown family's continued call for peaceful demonstrations, violent protests have erupted nearly every night in Ferguson since his death.  (Photo by Scott Olson/Getty Images)