In a bid to get the charges dismissed, Cosby's new legal team, headed by prominent Los Angeles attorney Tom Mesereau, accused the district attorney of prosecutorial misconduct. In return, DA Kevin Steele tried to get Cosby's out-of-town lawyers removed from the trial, saying their filing showed a "reckless disregard for the truth."
The fight revolved around a woman, Marguerite Jackson, who worked at Temple University at the same time as Constand and who says Constand once told her she could accuse a celebrity of drugging and abusing her for money.
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The defense took a statement from Jackson in November 2016, and it was turned over to the DA in April 2017, shortly before the trial. Investigators from the DA's office then interviewed Jackson and succeeded in blocking her from testifying.
Cosby's team alleged that Steele hid the fact that his office had interviewed Jackson and claimed the notes from the meeting were destroyed.
"They went and interviewed her, so they knew what she said completely repudiated Andrea Constand's statement accusing Mr. Cosby of misconduct," defense lawyer Kathleen Bliss said.
But Steele said Cosby's previous defense lawyer was fully aware of the interview and there's no indication that notes were ever taken.
The DA said the defense claims were "at best incompetent and at worst unethical" and urged the judge to deny a motion that would have allowed Mesereau and several other attorneys to represent Cosby in a Pennsylvania court.
The judge denied the defense quest for a dismissal but said the lawyers could stay on the case for now. He hasn't yet ruled on whether Jackson can testify at the retrial.
He also denied another defense motion for a dismissal on the grounds that the 12-year statute of limitations had passed.
Constand says Cosby gave her pills that incapacitated her and then sexually assaulted her sometime in January 2004. Pennsylvania prosecutors brought charges in December 2015, just under the deadline — after dozens of women had lodged misconduct accusations against the man once known as "America's Dad," who denies any wrongdoing.
But the defense says that while Constand testified that she called Cosby to be let into his estate on the night in question, her own phone records show no calls were placed to the house in January 2004. The judge said that was a matter for the jury to consider, not for him to decide before trial.
O'Neill has already announced he will not immediately rule on the most crucial matter before him: whether other women who say Cosby drugged and abused them can tell their stories to the jury to show a pattern of behavior.
The idea behind it is that the more something happens, the less likely it is an accident. By putting 19 other women with allegations similar to Constand's on the stand, prosecutors can argue that Cosby had to known exactly what he was doing when he gave Constand pills and that she was unable to consent.
"The defendant systematically engaged in a signature pattern," Assistant DA Adrienne Jappe argued. "It is improbable for him to be innocently enmeshed in this."
The judge has to weigh the value of the so-called prior bad act witnesses to the prosecution's case against the likelihood they would unfairly prejudice the jury against Cosby. His defense team will get a chance to challenge the use of the witnesses when the hearing continues Tuesday.
The two sides can't even agree on what to call the 19 women. The DA refers to them as "victims," and the defense says they should be called "accusers."
O'Neill said he will decide before trial. For now, he said, "call them what you want to call them."