NORRISTOWN • A Pennsylvania judge declared a mistrial yesterday after a jury was "hopelessly deadlocked" on sexual-assault charges against Bill Cosby, the comic legend whose legacy as a promoter of wholesome values has been tarnished by a years-long sex and drugging scandal.

As the mistrial was declared, Cosby sat at the defence table with his chin held high, a flat, blank look on his face.

Across the well of the courtroom, jurors stood one-by-one in the jury box and said, "Yes", as the judge asked each whether they agreed that the jury is "hopelessly deadlocked".

The jurors answered without hesitation, but several slumped forward in their chairs, elbows on their knees and fingers knit, with looks of frustration on their faces.

After the questioning was done, the entertainer sat back in his chair, holding a slender cane that has been with him inside the courtroom each day to his chest.

After the jury filed out, prosecutor Kevin Steele announced in court that he will retry Mr Cosby.

The jurors, who had complained of exhaustion, deliberated 52 hours before finally saying they could not reach a verdict on three counts of aggravated indecent assault against the 79-year-old entertainer.

But the hung jury does not end Cosby's legal troubles because he could be retried on the same charges and is still facing lawsuits filed by some of the 60 women who have accused him of sexual assault, rape or sexual harassment.

As deliberations dragged on, signs of discontent in the jury room kept emerging.

The jurors, who had been kept working 12- and 13-hour days by Montgomery County judge Steven T. O'Neill, who oversaw the case, since beginning their cloistered discussions on Monday afternoon, wanted to go back to the hotel early on Tuesday. The next day they expressed "concerns" to court officials, though the judge did not reveal the substance of their complaints.

Defence attorneys furiously demanded a mistrial many times in the courtroom during the lengthy deliberations, but Judge O'Neill insisted on letting the jury continue its work.

Late on Thursday morning, just after passing the 30-hour mark in deliberations, jurors formally announced for the first time that they were deadlocked in a one-sentence note, saying they could not reach a "unanimous consensus" on any of the counts.

The judge gave the standard order to keep trying, but they were ultimately unable to break the deadlock.

When he first heard about the deadlock, Cosby walked out of the courtroom with a smile on his face.

The jury seemed to take an unusually painstaking approach to deliberations, asking to rehear testimony from half of the prosecution witnesses and to look anew at evidence.

The requests amounted to something akin to replaying the entire trial. And, by the end, jurors had deliberated for far more hours than the length of testimony, opening statements and closing arguments combined.

The conclusion of the trial, to an extent, softens one of the most thundering falls from grace by a popular culture figure in recent American history.

Cosby's starring role as beloved dad Heathcliff Huxtable in The Cosby Show made him a household name, bolstering a reputation built on years of family-friendly comedy. Still, testimony in the case further sullied Cosby's image as "America's Dad", with jurors hearing of his frequent infidelities.

His accuser, Ms Andrea Constand, 44, a former Temple University women's basketball employee, testified that Cosby sexually assaulted her in 2004, manipulating her into taking pills that left her "frozen" and unable to stop him from touching her breasts and genitals during an evening at his suburban Philadelphia estate.

At the time, Cosby sat on the Philadelphia university's board of trustees. He has said that he gave Ms Constand only Benadryl.

WASHINGTON POST, REUTERS, NYTIMES