A police officer holds his riot gun while demonstrators protest the shooting death of teenager Michael Brown in Ferguson, Missouri

A police officer holds his riot gun while demonstrators protest the shooting death of teenager Michael Brown in Ferguson, Missouri

A police officer holds his riot gun while demonstrators protest the shooting death of teenager Michael Brown in Ferguson, Missouri August 13, 2014. Police in Ferguson fired several rounds of tear gas to disperse protesters late on Wednesday, on the fourth night of demonstrations over the fatal shooting last weekend of an unarmed black teenager Brown, 18, by a police officer on Saturday after what police said was a struggle with a gun in a police car. A witness in the case told local media that Brown had raised his arms to police to show that he was unarmed before being killed. REUTERS/Mario Anzuoni (UNITED STATES – Tags: CRIME LAW CIVIL UNREST)