Just to give a bit different perspective (and no way endorsing anything about MJ or saying what is in the report is true or not). A very close family member of mine was accused of something similar. His SO made the same accusations, had marks on her arms (he had far more on his body though) and her mother backed up her claims. The police report also had a very slanted report from the interviews.
It later transpired that she lied about what happened and admitted it, her mother lied about what happened and all because she was simply pissed at him and attacked him by jumping on him when he tried to deescalate the situation and stop her coming into the room, hence the marks. The mother hated him and was quite happy when he got arrested.
In the end, all the charges were dropped, and I am just glad none of this made it into the public for him. Because it is damaging, and no one believes you (including me at the time). So, I prefer to wait. If he is guilty, he'll pay for it. If not, that will come out as well.