In the wake of three high-profile police shooting trials, criminal justice experts told NBC News that it is extremely difficult to convict a law enforcement officer for a fatal shooting.
A pair of Supreme Court rulings from the 1980s puts the law on the side of the police, particularly if they believe they are in danger of death or serious harm. Two of the recent cases, the fatal shootings of Philando Castile and Sylville Smith, hinged on questions of "reasonable fear."
"For better or worse, whether you believe in it or not, [the law] is very favorable to police use of force," said David A. Harris, a law professor at the University of Pittsburgh. "That objective standard is very wide in terms of giving police discretion."
But civil rights advocates say that the wider social issue is implicit racial bias, the idea that everyone holds subconscious racial prejudices — including people in positions of supposed impartiality, like police and judges.