I would like to think that people treat others how you would expect to be treated, I know that's naive, but I've not really come into problems with the police, but I know there are some knobs on a power trip out there. A mate had a White van just with some alloys on, all declared and the police stopped him, cuffed him and ripped the van apart searching for drugs, finally worked out it was the wrong van and just left him, doorcards had been taken off, carpet and everything!
I agree with what's been said if you are unhappy with how your case/circumstance has been dealt with, make a complaint, I'm led to believe that everytime they pull someone they inform someone so there's an auditable record, so you should be able to find out who it was if you didn't get a shoulder number.