Forget the Police
Sure they already have access and use it in lots of totalitarian places to determine who needs beating.
However this gives amazing help to anyone in the private sector to mean to pay for a surveillance team. Sure it isn't perfect but its a lot better than nothing. All I now need is access to an individuals phone and I can start to build valuable data. Give me access twice and I can clean the file once and start to build a detailed picture of what happens between accesses.
Are you concerned ,your employee is interviewing for a job elsewhere, that your wife or husband is not telling you the truth, or that your aunt Mabel is wasting your inheritance at the dog track?
Those people who trivialise this are plainly stupid, it is a bad thing which will be used for bad purposes.