My question involves criminal law for the state of: Texas.

My brother recently attending an event where he was attacked by a group of boys much larger than himself. While defending himself against his attackers, he was attacked from behind by a police officer servicing the event of over 800 attendees. Still defending himself, the police officer was hit in the crossfire. The officer arrested my brother for assault on a peace servant, and he was taken to the county jail. He was beaten repeatedly by the police officer, while only stating that he did not intentionally hit him. The officer had absolutely no injuries, and there were no cameras at the event. No pictures or evidence was taken. After trying to help my brother, I too was assaulted by a fellow officer who refused to give me his name nor badge number. After being placed in county, my brother saw a judge who set his bond at 25,000. Mind you, my brother has absolutely no criminal record, has never been arrested nor to jail, and has absolutely no warrants. I have evidence that shows my brother was beaten repeatedly, as well as statements by attendees stating my brother did not commit the crime he has been charged with. What will happen most likely in court?