I believe Dylan Farrow.
Almost every time I am going to believe the victim rather than accused, when it comes to matters of rape, sexual abuse, abuse of power, and the like. I think it's important to redress the massive power imbalance in these cases by giving more weight to the voice, the story, the experiences of the victim. I believe Louise Nicholas too.
I understand that the way the justice system works is different. Due to the presumption of innocence, currently it seems impossible to give anything approaching equal weight to victim and accused. Ironically, what does serve to provide some balance are other prejudices coming in to play. The version of the victim will be considered more believable if they are cis female, white, "presentable", middle-class, virginal/married to someone other than the accused, acted in accepted ways before, during and after being assaulted/abused. The version of the accused will be discounted in part or whole if cis male, physically powerful, brown, a stranger to the victim, poor, shown to be non-vanilla in sexual preferences and practices.
I can form a different opinion from the verdicts the justice system produces. I can make up my own mind. It has no consequences for the legal outcomes if I do.
But, if I can express my belief in the victim and their story in a way they become aware of, or other victims and survivors become aware, then I'm hopeful I'm expressing some solidarity, some support, for them. That in some small way I am helping to redress the tilt the justice system applies, on a social level if not a legal one.
Comment direction: I am not interested in debating my central premise here in the comments below, as I believe that could be very harmful to readers. I'll be deleting comments that denigrate victims, propose that the accused in these cases is the underdog, anything like that. I am interested in discussion of how we make the justice system fairer in these contexts, up against the (important) presumption of innocence of the accused, and I have no easy answers on that.