They deliberated more than 50 hours and still could not reach a verdict.
Brian McMonagle, one of Cosby's lawyers, addressed the jury, "We came here looking for an acquittal but like that Rolling Stones song says, 'You can't always get what you want".
And in a scathing statement read aloud by a representative, Cosby's wife, Camille, called the the district attorney "heinously and exploitatively ambitious" and the judge "overtly and arrogantly collaborating" with him - among other allegations.
The prosecution also said they will revisit their petition to have 13 of the more than 50 Cosby accusers testify in the retrial.
McMonagle had sought a mistrial seven times during the deliberation phase, arguing jurors were asking to review the entire trial.
Prosecutors said Cosby, 79, drugged and sexually assaulted Andrea Constand, the former director of operations for Temple University's women's basketball team, at his home near Philadelphia in January 2004. Judge Steven O'Neill advised jurors when the trial ended on Saturday outside Philadelphia, after a week of testimony and 52 hours of deliberations, that they need not discuss the case, even as the public debates whether age, race, gender or other issues separated them.
More important for future victims is to remove the cultural and legal obstacles - from celebrity worship to court secrecy - that still make it too hard for women to get justice after they've been sexually assaulted. He did, however, advise them that speaking publicly about the case could cause problems in the case of a new trial, which prosecutors have vowed is coming.
"The commonwealth's and the defense's extensive public comments about the case - including about evidence that the jury never heard - before, during, and after the trial will have a far greater impact on that process than would the comments of a few jurors", he wrote.
Mike McCloskey, one of six alternate jurors chosen for the almost two-week trial, discussed his experience in an interview with Pittsburgh radio station WDVE. "We didn't even get a decision so that made me more sick". "It was complete silence".More news: Chinese tour agency axes visits to North Korea for USA citizens
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"It was the craziest, eeriest bus ride I've ever taken."
Given the judge's sealing order, McCloskey's status as an alternate could not be independently verified.
The jury on Saturday deadlocked on charges that Cosby drugged and molested a woman in 2004, resulting in a mistrial.
"I felt like we let Andrea down", he said. "He just assumed, I'm Bill Cosby", McKee told the Los Angeles Times earlier this month.
Constand is on board for the retrial. Cosby maintains the sexual encounter was consensual.
"It was ridiculously creepy", McCloskey told WDVE. Although he gave the jurors this instruction, one alternate who did not decide on the outcome spoke to NBC News.
"I devoted two weeks of my life sequestered in Norristown, PA, which, if you've ever been to Norristown, it's disgusting".
Though they were allowed access to televisions and the internet, they were instructed not to look up any outside accounts about the case and were polled each morning by the judge to ensure they hadn't been accidentally exposed to any such information.