It's hard to know what conclusions to draw from this case. I admit to really liking JD at one time. I think it's fair to say he's a complex character, and by his own admission spent periods of his life, off his face.
I think some people can just bring out the worst in each other. Previous partners have testified in his defence as to not knowing this violent side of his character, perhaps they are right, in that they never saw that side of him. Vanessa Paradis would have known him well they spent quite a long time together and that partnership produced 2 children. In fact if anything she could have bad mouthed him as I gather he had his head turned by Amber Heard when they were still together, but she has been steadfast in her assertion that he was a nice person when he was with her. That of course doesn't mean that he hasn't abused AH, clearly he has been recorded saying some pretty vile things about her. She also said, I believe, that he pushed Kate Moss down the stairs, I think KM is admirably a "never complain and never explain" type of c'leb, so I don't think she's made any comment about that one way or the other.
Neither of them come out of this well. I think it's possible he may have become violent in this relationship. I think it's also possible that she may also be violent and as such their relationship degenerated into what it became. It is a fact that sometimes women abuse men, but less common of course than the other way round.
I don't agree with women booing and hissing at AH, none of us knows the truth or how the dynamics of their relationship played out. It is quite possible to be nice and kind in some ways, I heard he made a large donation to Great Ormond Street when his daughter was in there, but still be awful in other ways.
I will reserve judgement.