FBI Director James Comey has called on police nationwide to confront what he said is unconscious racial bias in the wake of a spate of killings of unarmed African Americans. In an unprecedented speech for an FBI chief, Comey said the nation’s “endemic” racism must be addressed.

James Comey: “Much research points to the widespread existence of unconscious bias. Many people in our white-majority culture have unconscious racial biases and react differently to a white face than a black face. … Police officers on patrol in our nation’s cities often work in environments where a hugely disproportionate percentage of street crime is committed by young men of color. Something happens to people of goodwill working in that environment. After years of police work, officers often can’t help but be influenced by the cynicism they feel. A mental shortcut becomes almost irresistible, and maybe even rational by some lights. … We need to come to grips with the fact that this behavior complicates the relationship between police and the communities they serve.”

Comey is known to keep a copy of the FBI’s wiretap order targeting Dr. Martin Luther King Jr. as a reminder of the agency’s past misdeeds.