My argument is that the jury may see their relationship as "mutually abusive". Most stuff happened behind the closed door and both claimed to be the victim. It'll be very hard to prove otherwise even though one might have slightly better evidences than other. For the common folks, things always make more sense when one is the aggressor and other is the victim but any relationship expert will tell you it's not that simple and I believe that's what jury' leaning torward to.
My 2nd argument is about the "defamination" lawsuit . Depp has to prove that 2018 article that Amber' team wrote, damaged his public image and she did it with no other intention. This point out to my first point, if Jury see this as a mutually abusive relationship then what she said was "partially correct" and she did it just to PR her new movie etc...He's the plaintiff, he's the one that has to prove things in court.
With that being said, I believe Depp's trying to win public's opinion, not the lawsuit itself. Depp might not be a saint but noone deserves to be cancelled just because another person shit in his bed.