How old is your brother?
If they let you get off easy this time then you should educate him like Krid said.
But if you go to jail because of him then it is your duty to beat the shit out of him.
Well it doesn't impair his driving because he's an old burnt out sonofabitch. And we all know what horrible drivers old people are. So when he goes out, getting rear ended and pulled over a couple of times isn't anything out of the ordinary for him.