There are all sorts of powers we afford law enforcement that could be abused; I hardly think cameras would be at the top of the list of concerns, honestly. NYC has had thousands upon thousands of cameras for quite a while without much fanfare, along with other major top cities worldwide.
They are abused.
They can be abused in the future even more.
Mass surveillance is abuse within itself.
There has been controversy in NYC.
No controversy doesn't make things right.