I don't believe they are "lieing" or "cheating" but are simply rather mistaken and going on the facts that they have. As you said your brother is the guilty one, do you two look similar enough that you may easily be confused for one another when going 30+mph on a bike? Its a shame, but hopefully you can get it figured out or atleast have your brother take responsibility for his actions. If he won't, then get whatever evidence you can and explain to the court that it was your brother that commited the violation.It's was a 2vs1 case, I've never done this sort of thing before and they had 2 cops fighting against me. I bet they can sleep at night knowing they lied and cheated to ruin someone's future.