Philly Touts Cameras in 37% Crime Drop

Philadelphia is aggressively adding city surveillance cameras, 250 of them, after the success of its initial rollout of just eighteen cameras last year.

The city installed 18 video surveillance cameras last year, which resulted
in an 8.4 percent decline in reported crime at 8 of the locations and a 37
percent decrease in violent crimes. (via Philadelphia Business
Journal)

I think Philly's aggressive monitoring and prosecution efforts might have had a little something to do with the decrease too.