Jumping on this top comment to provide some context. As a divorce attorney in Nassau county I'm very familiar with the law and this particular case. I know the judge and most of the attorneys involved.

What happened here is shortly after (if I recall maybe a year or so) the parties were back in court seeking to modify an agreement that provided for joint legal custody and shared parenting time. There were numerous allegations on both sides that are not mentioned here, including Bill trying to have his ex wife excommunicated from the Catholic Church and hiring an agreed upon neutral parenting coordinator to essentially be a pseudo parent during his parenting time. The violent incident in question stems from prior to them signing an agreement pursuant to which they agreed to share custody. That allegation would not constitute a substantial change in circumstances occurring after they signed the agreement. It's limited relevance goes to one of the reasons why the teenage daughter apparently did not want to spend as much time with her father.

This article has the exact quotes from the transcript, which should NEVER have been leaked in the first place. Someone in the court system has been leaking stuff for years in this case and I reluctantly share it so everyone can see. The allegation was made by the daughter to the neutral forensic psychologist, who then testified to it in court. It's hearsay. At the end of the trial, usually the judge conducts an off the record conference in chambers with the children and their attorney to get their perspective and consider their wishes.

http://gawker.com/court-transcripts-bill-o-reilly-s-daughter-saw-him-ch-1704717356