The jury in Bill Cosby's sexual assault case ended a fifth day of deliberations Friday without reaching a verdict, testing the patience of defence lawyers and even the judge as it struggled to break a deadlock by making repeated runs through testimony given by the TV star, his accuser and others.

With deliberations passing the 50-hour mark — longer than the testimony of all the witnesses combined — the 79-year-old TV star's lawyer complained that jurors were seeking a replay of the entire trial. Lawyer Brian McMonagle also worried that some jurors might compromise "their views and their values" for the sake of reaching a unanimous decision.

"I believe this jury is tired, is weary," McMonagle said late Friday, as the jury wrapped up yet another marathon round of deliberations. "I believe they are being compelled to come back with a verdict."

Judge Steven O'Neill refused repeated defence requests for a mistrial, declaring that jurors could talk as long as they wanted over allegations that Cosby drugged and molested a Canadian woman at his suburban Philadelphia mansion in 2004. The judge had instructed the panel to keep deliberating after it reported Thursday it was deadlocked on the charges against the comedian.

But even the solicitous judge had his limits, putting his foot down late Friday afternoon when the jurors asked to hear a sliver of testimony they'd just had read back to them. The judge told them they had to rely on their collective memory.

Cosby faces 3 charges of indecent assault

As the panel deliberated charges that could send Cosby to prison for the rest of his life, Cosby tweeted thanks to his fans and supporters. 

The entertainer, once known as "America's Dad," offered Father's Day greetings to well-wishers outside the courthouse after the jury adjourned.

"I just want to wish all of the fathers a happy Father's Day," Cosby said. "And I want to thank the jury for their long days, their honest work, individually. I also want to thank the supporters who have been here. And, please, to the supporters, stay calm. Do not argue with people. Just keep up the great support. Thank you."

The case has helped demolish Cosby's nice-guy image, cultivated during his eight-year run as Dr. Cliff Huxtable on the top-rated The Cosby Show in the 1980s and '90s.

Dozens of women have come forward to say Cosby drugged and assaulted them, but this was the only case to result in criminal charges. 

On Friday, the jury asked to review multiple pieces of evidence, including Cosby's 2006 deposition testimony about quaaludes, a now-banned party drug.

Cosby, who gave the deposition as part of Andrea Constand's lawsuit against him, said he got seven prescriptions for the powerful sedative in the 1970s for the purpose of giving them to women with whom he wanted to have sex.

Jurors hear definition of 'reasonable doubt' 

The testimony is relevant because Cosby is charged with giving pills to Constand, a former Temple University employee, to incapacitate her before their sexual encounter. He has said it was Benadryl, a cold and allergy medicine. Prosecutors have suggested he gave her something stronger, perhaps even quaaludes. 

The jurors also listened to the definition of reasonable doubt, the threshold that prosecutors must cross to win a conviction, and reviewed testimony from Toronto's Constand and her mother about phone conversations they had with Cosby after the encounter.

According to the testimony, Cosby called himself a "sick man" but refused to identify the pills he gave to Constand.

Bill Cosby

Cosby is accused of drugging and sexually assaulting Canadian Andrea Constand at his home outside Philadelphia in 2004. (Matt Rourke/Associated Press)

Cosby's lawyer, Brian McMonagle, has said Cosby and Constand were lovers sharing a consensual moment of intimacy. 

McMonagle objected in court to the panel's repeated requests to review testimony, saying it suggested some jurors were trying to coerce other jurors in an attempt to bring an end to the deadlock.

Jury must come to unanimous decision

The judge said he saw no evidence of coercion or trouble in the deliberating room after the jurors reported their impasse on Thursday and he instructed them to keep trying for a verdict. 

"There's a misperception that there's a time limit," the judge said.

The panel got the case on Monday. It must come to a unanimous decision to convict or acquit.

Bill Cosby

Bill Cosby waves as he arrives for his sexual assault trial at the Montgomery County Courthouse in Norristown, Pa., on Friday. (Lucas Jackson/Pool Photo via Associated Press)

If the panel can't break the deadlock, the judge could declare a hung jury and a mistrial. In that case, prosecutors would get four months to decide whether they want to retry Cosby or drop the charges. 

The Associated Press does not typically identify people who say they are victims of sexual assault unless they grant permission, which Constand has done.