It was not proven, but he stood trial for the murders of his ex-wife, Nicole Simpson, and a waiter, Ron Goodman. Nicole was a grown woman with two preteen children at the time of her murder; if you are thinking of a young girl, then I don't know that story.
Orenthal James Simpson (nicknamed the juice) was charged with the murder if Nicole Brown. Link enclosed.
Nicole Brown Simpson
Nicole Brown Simpson and Ronald Lyle Goodman (FYI, he was acquitted, so he wasn't exactly proven to be the killer, but then)
