As a mere 'civvie', I can second Irene's informed professional views with those of one who sees things from the 'other side', so to speak.
British Bobbies do an excellent job under increasingly difficult circumstances. All you have to do is follow a couple of simple rules:
1) Don't break the law (even the dumb ones)
2) Don't use your cheek - they're vastly tolerant (far more than I would be) but there are limits.
The concept of 'rights' is a tricky one in Britain, as I've mentioned before. Generally speaking, we have what 'rights' the government of the day decides we have, subject to the approval of the Crown. People, especially youngsters who have grown up on a diet of American TV cop shows, have some misguided ideas about 'rights' to go with the very real (and absurd) over-protection they have from the consequences of their actions.
When it comes to being questioned by a policeman/woman, it serves you far better to "Yes sir/mam" it than argue the toss. Co-operate and the worst you suffer is a bit of inconvenience (and the sense that your taxes are doing some good) - so why kick up a fuss?
I know this must sound really odd to our much 'freer' American friends because you have legally defined rights and powers enshrined in your Constitution (how's the dissolving of that going by the way?) but to us Limeys it's no big deal to be 'oppressed by the man'

. It's been the same for a long time - at least now they don't use sabres on us

.
The big counterbalance, to elaborate, is the Crown itself. The government gets
too out of bounds and Mrs. Queen can quite legitimately sack the lot of them. If they don't like it then it's a bit tough for them because the military swear their oathes to the Crown, not the government. So as long as we've got a decent King/Queen we're okay :tup:.