exactly... dude sue them, at least try if you have some time. thats the only way we can make thing change. for the princip of it, you should sue.. i dont know how it is in your fucked up country but in canada they have to tell us what are we arrested for before they put the handcuffs on .. if they dont then you have a chance.
but just a question.. what were you doing taking pictures of graffiti at 12h in the night? dayshots would ve been better..no...?