While they sparred with him in court Thursday, Cosby's lawyers are also counting on him to make critical rulings to bolster their defense that Constand is a money-grubbing liar.
They want O'Neill to let them call Marguerite Jackson, a woman who says Constand spoke of framing a celebrity before she went to police with allegations that Cosby drugged and molested her in 2004. They also want to let jurors know how much Cosby paid her in a 2006 civil settlement.
"Those are the bookends: I have a motive and I have a payoff," lawyer Kathleen Bliss argued. "The jury should be allowed to view the full context of that."
Assistant District Attorney Kristen Fedden said that they doubt the discussion with Jackson happened and Constand's lawyer has said that Jackson is "not telling the truth."
O'Neill blocked Jackson from testifying at the first trial because he said her testimony would be hearsay. Prosecutors want him to do the same for the retrial.
Prosecutors say the theory that Constand wanted to set up Cosby is undermined by the comedian's testimony in a 2005 deposition that she only visited his home when invited and that he gave her pills without her asking for them.
Prosecutors also argued the settlement is irrelevant to the criminal case, but that if it is allowed in, jurors should also hear about negotiations that led to the settlement.
Assistant District Attorney Stewart Ryan contended that Cosby's negotiators initially asked that he be released from any criminal liability and tried to bar Constand from cooperating with law enforcement. He said that amounts to obstruction of justice.
"Those things are inconsistent with a person who believes he's innocent," Ryan said.
Thursday's hearing started with arguments over the judge's wife, Deborah O'Neill, a psychotherapist at who coordinates a team that cares and advocates for student sexual assault victims.
O'Neill said that the donation cited by Cosby's lawyers didn't involve her money or their joint assets.
"How are my wife's independent views of an independent woman connected to me?" O'Neill said. "She's an independent woman and has the right to be involved in anything that she believes in."
O'Neill said Thursday that Cosby's old lawyers raised the prospect of having him step aside in December 2016, but never followed through. He added that he could've rejected the recusal request simply because Cosby's lawyers waited too long to ask.
He said they were aware of Deborah O'Neill's work as far back as December 2016, but that they waited until getting several adverse rulings just before retrial to raise it as an issue.
O'Neill spoke glowingly about his wife and said it was difficult to have her accomplishments "trivialized" in a legal motion. He said Cosby's lawyers had presented an antiquated view of marriage where spouses must agree on everything.
Cosby's lawyers could still appeal O'Neill's decision to allow the other accusers to testify to the state's Supreme Court.
The pretrial hearing will continue Friday, including for arguments over whether jurors can hear about a 2005 phone call in which Constand says she told her mother about the alleged assault for the first time.
O'Neill agreed Thursday that the trial won't start until at least April 9 and that the jury chosen from suburban Montgomery County will be sequestered in a local hotel.
The AP does not typically identify people who say they are victims of sexual assault unless they grant permission, which Constand has done.