You’ve never played with a chain link fence, eh? They’re really heavy, especially in long sections and when you let them fall back down (like after you’ve been holding the bottom up so your friends can crawl under) they just kinda flop back into position. The individual strands absorb the energy of the hit and it just kinda ripples across a section or two. It doesn’t act at all like a solid panel fence made from wood. These flexible strands also make it really hard to bend the fence, especially if you move a panel with nothing holding it back.
I agree, the cop should have run through the fence and after the guy. He probably would have damaged the light bar on the roof but he wouldn’t have been slowed down too much.