I'm in the jurisdiction of Lothian & Borders police and despite a couple of the officers being real jerks*, the majority are really nice, friendly folk who do a pretty good job, considering that, where I live, they are GROSSLY undermanned and overstretched. There is (and I joke you not) one officer supposed to be patrolling three (admittedly smallish) towns, several miles apart, on a weekend night when a lot of people go out drinking and start fights; this is because of budget cuts; management decided to axe a lot of local spending so they could have a nice new academy and offices in Edinburgh, or something along that line. By and large I've found my local Force pretty decent folk...
*...and now for the officers who are total jerks...
Example 1: The son of a work colleague (who was 14 at the time) was arrested and detained in a holding cell for 5 hours without being told why he had been arrested and wasn't allowed to contact his parents because apparently he first had to have an interview with a legal representative present first. Then his mother was called to pick him up and he was released without charge; apparently he had been mistakenly identified as someone much older than him who had apparently held someone at knifepoint after an argument. He was never asked to show any identification when approached by the police and they never bothered to check his identity when he was arrested.
Example 2 (and this one really takes the cake): A group of my friends had met up in a local park; the police drove up, physically restrained one of them and put him in the back of the car. When queried why they had arrested him, the officer turned to them, shouted "ILLEGAL!!!" and then drove off; they took him to his house, opened the car door, let him go and drove off without a word. I mean come on, what the heck that besides some weird power trippy thing.