Any officer killed in the line of duty is a bad thing. But criticism by Obama and his administration of dubious killings and such by some police officers isn't in turn triggering some systemic wave of shootings of police.
Not that anyone should pay any attention to anything Scott Walker says, of course.
(That downward line, by the way, parallels the general direction of violent crime in the US as a whole as well, despite fear-mongering about increasing violence from folk who have an interest in people being scared.)

