Reading this thread is interesting.

I believe I have a pragmatic approach to the police; I'll try to go along with them as much as possible, as politely as possible, even if I know they might have iffy legal grounds to do so or are asking me to do something that doesn't make sense. I also believe that if I break the law -no matter how seemingly trivial -then, well, I've broken the law and I cannot expect anything less than what would be legally set down for the offence.

As I said, I believe I'm pragmatic -it's fine getting all up in arms when a police officer acts the bully, goes power hungry or infringes on your legal rights to some extent, but the bottom line is (however rightly or wrongly) they are the "law" at that point in time and location, and they can or will make things far more difficult for you. That doesn't make it right, of course.

Another aspect to consider is if it ultimately ends up in a court, more than likely it's going to be your word (scraggly cycle tourer) versus an upstanding police officer. Who do you think a judge or a jury is going to believe? Let's face it, unfortunately life's not fair!

I'm of the opinion that if an action outrages you that much, you're always going to have much better results taking this up with the officer's superiors or some other official or unofficial channel once you're removed from the situation. It also gives you time to calm down, think about what you wish to get out of the situation, how you're going to pursue it, and whether it's ultimately worth it to you.