Judging by the videos which clog the back end television channels the use of police helicopters has little benefit apart from producing video where the headless voice can proclaim how dangerous the continuing high speed pursuit is.
If helicopters were used to allow police cars to stop chasing then they would represent a major improvement in the safety of the public. These videos however prove that is NOT what is done - instead it is a high speed chase usually through built up areas and an expensive aerial video at the end of it.
I'm left with a general feeling that in the vast majority of cases police helicopters are a vanity project. a view which is largely confirmed by media stories of a cetain police helicopter tracking a woman in a car who was charged with eating an apple.........