Is There a Silver Lining to the Police Killings in Memphis?

John Avlon: I think the action that the city's taken will help. There was a spike in police killings last year, but that comes in the context of a fairly long-term decline in the numbers of Americans being killed by police officers. He says it's possible to look at cases like tiring impulses and assume that there's more of this stuff happening than used to be the case.