Policing the riots and criticising the police

I am hearing a lot of criticism of the police as the dust settles in the wake of the recent riots. This strikes me as particularly knee-jerk and opportunistic. I saw a lot of scary scenes from the comfort of my front room and I saw a lot of people's lives being torn apart by thugs and criminals and mindless morons but the one thing I didn't see was police lounging round doing nothing.