I would have used "few" myself a number of years ago. And 50 years ago I wouldn't have even used the expression. And I guess it depends on what your definition of a "criminal" is, But over the last 50 years I've seen a lot more hostility directed at the police. Some of it deadly. Just within the last five years, in a number of communities throughout the country, cops have been shot at randomly and while just sitting in their patrol car. I don't remember that happening anywhere near the frequency that it is now. Locally, Officer Kilcullen was shot and killed. I know the woman who did it is mentally ill, but people are influenced by the world we live in, 
Recently and not deadly - Bottles and rocks thrown at police a couple of weeks ago in Portland. EPD encountering a hostile (and eventually violent) crowd for doing their job by arresting a fighting, out of control person at the downtown bus station. This cop on River Road.
I don't like the direction things are headed regarding cops.