I don't think he's be found guilty of anything. They investigated, a few of his former team mates came forward and said some stuff. They - the US cycling federation or something - charged him. He contested the charges.
LA had a titfull and said he's not going to contest the charges. BINGO, they find him guilty!
So their position is that he has to prove he's innocent, rather than they having to prove his guilt.
I've not read too much into the history of the allegations of his former team mates, but just what's been in the news recently, stuff about blood transfusions when he had cancer.