Prosecutors said they will retry the case.
One of the most popular television series in history, it propelled Cosby - a man raised by a maid and a US Navy cook - into a life of fame and wealth.
Constand alleges she then became incapacitated and was led to a couch, where Cosby is alleged to have fondled her breasts, put his hands inside her trousers, and penetrated her vagina with his fingers. "You're not going to want to start a war with someone way higher on the food chain", she said.
A statement from Cosby's wife, Camille, that was delivered by a spokeswoman called the presiding judge and district attorney "totally unethical".
While walking out of the courthouse Saturday, Cosby's spokesperson Andrew Wyatt praised what happened Saturday, adding that "Mr. Cosby's power is back. But why keep costing these citizens millions of dollars?" Cosby admitted to obtaining the prescription sedative to give to multiple women with whom he wanted to have sex, and said that he didn't take the drug himself.
"The day has finally come that now the world can see first hand why so many survivors of sexual assault, domestic violence and rape wait to report", began a lengthy statement from accuser Beth Ferrier.
"There was no pause or hesitation about that, and we're moving forward", he told reporters. "For the trial that just ended, the court only allowed one such prior bad act witness to testify".
"You don't know why they were deadlocked". Cosby previously admitted to police that he gave women Benadryl, as Constand claims he did to her, and quaaludes, before attempting to have sex with them. But in most of those cases, the statute of limitations had expired by the time the women told their stories publicly.
It was the statement Cosby made in a deposition to Constand's lawyers in his lawsuit in 2005 that led Pennsylvania prosecutors to charge him in the Constand case. Cosby faced three charges of aggravated indecent assault.
NY lawyer Paul Callan, a former prosecutor, said he thought it would "exceptionally difficult" for the state to win a second trial against Cosby.
Jewell Allison, who alleges that Cosby drugged and assaulted her in the late '80s, had a spiritual response to the case's outcome. Cosby did not testify in his own defense.
Dunham's colleague, "Girls" director and filmmaker Richard Shepard, tweeted a photo of the New York Magazine cover featuring several of Cosby's accusers.
Actor and comedian Bill Cosby looks on as his lawyer Brian McGonogle addresses the media outside the Montgomery County Courthouse on June 17, 2017 in Norristown, Pennsylvania. "And I want to thank the jury for their long days. And the jury stuck to what they were asked to do and that is to review the evidence before them and there simply wasn't enough".
On Thursday, after more than 30 hours of deliberations, the members of the jury told the judge they were deadlocked and could not reach a unanimous consensus.
If they can't break the deadlock, O'Neill could declare a hung jury and a mistrial.
NPR host Scott Simon filled the airtime by saying Cosby was just "shaking his head no".