Didn't he also say he cut off his own finger? and his black eye photo is just as questionable as hers, isn't it? there is no evidence of either-or.
Good questions. He says the bottle cut his finger off when she threw it. She says a phone smashed his finger. Where it gets interesting is a witness claims that Amber told her Johnny cut it himself when a bottle he was playing with broke. So it would seem that she told a different story to a witness than she did in court.
And if memory serves, there are at least two photos of Depp at public appearances with a black eye. Heard was only seen in public with a mark on her face once, and that's the day she went to get the restraining order. A former TMZ guy testified on that day they knew where and when she was going to be getting that restraining order, and which side of her face to photograph. She was photographed publicly again the next day with no bruising on her face. There's also evidence she edited the photos she did have, although not all of it was admissible in court. The photo expert on the Depp team was not allowed to talk about certain aspects of color adjustment and such.
I don't blame people who haven't seen much of the trial for thinking it all sounds like a mutually toxic relationship, because I would have probably thought the same thing had I not watched the trial.
[edit] Here's what I was referring to. It was a great moment in the trial that didn't get a lot of notice. It just hints at the evidence the photo expert wasn't allowed to discuss, and only did so because Heard's team asked about it in a round about way and then quickly regretted it. The witness was kind of chuckling and shaking his head as if to say "you're actually asking me about the things I've been told I'm not allowed to talk about!? Okay, let's see where this goes."