Bill Cosby Assault Case: Former DA Testifies in Court

Former Montgomery County, Pennsylvania, District Attorney Bruce Castor explained to a judge today why he did not press criminal charges against famed comedian Bill Cosby a decade ago.

Cosby and his legal team are trying to dismiss the charge of aggravated indecent assault that First Assistant District Attorney Kevin Steele charged him with last December. Cosby, 78, has denied any wrongdoing.

Cosby, dressed in a brown suit, was flanked by security as he entered the court around 9 a.m. this morning. Judge Steven O'Neill denied the prosecution's request to postpone or shut down the hearing.

Castor was the first witness the comedian's legal team called to the stand. Castor claims he made an oral agreement not to criminally prosecute Cosby on a case stemming from a 2005 claim involving accuser and former Temple University employee Andrea Constand.

Castor gave three reasons why he didn't bring criminal charges against Cosby in 2005: it took Constand almost a year to come forward; the inability to collect forensic evidence; the fact that Constand contacted a civil lawyer in Philadelphia before going to police in Canada to file a report.

Castor further explained that Constand's "actions...created a credibility issue for her that could never be improved upon." He said the statements from other alleged victims were "very old" and noted that these individuals "had never gone to police."

ABC News reached out to Constand's lawyer Dolores Troiani for comment. Constand's legal team filed a defamation lawsuit this past October against Castor. Constand claims the former DA had defamed her by making various statements about her credibility to the media last year, according to paperwork obtained by ABC News. Constand's lawsuit says that Castor told the media he considered Constand's allegations to be a misdemeanor, for which the statute of limitations had expired.

Constand goes on to say in her defamation lawsuit that when Castor learned the current District Attorney was considering a felony prosecution against Cosby, which would show the statute of limitations had not expired, Castor chose to make Constand "collateral damage for his political ambitions," according to the suit.

In his answer to Constand's lawsuit, Castor denies those allegations, adding that the statements he's made about Constand are true.

Cosby and Constand eventually settled a civil lawsuit.

Constand said she and Cosby became friends while she worked at Temple more than a decade ago. She alleged that Cosby invited her to his home, where he made two sexual advances despite her rebuffs. She also claimed the comedian gave her pills and wine, which made her unresponsive and unable to move. At that point, she claims Cosby sexually assaulted her.

U.S. District Judge Eduardo Robreno unsealed Cosby's deposition in the Constand civil case last year, which brought new information to light, including Cosby's admission that he gave Quaaludes to one woman in the past.

When Cosby was charged late last year, First Assistant District Attorney Kevin Steele said, "We examined all the evidence and we made this determination because it was the right thing to do."

Cosby's attorney, Monique Pressley, previously responded to the charge in a statement to ABC News.

"The charge by the Montgomery County District Attorney's office came as no surprise, filed 12 years after the alleged incident and coming on the heels of a hotly contested election for this county's DA during which this case was made the focal point," she said. "Make no mistake, we intend to mount a vigorous defense against this unjustified charge and we expect that Mr. Cosby will be exonerated by a court of law."

Cosby has been accused by dozens of women of sexual misconduct over the past two years. Cosby fired back in early December, filing a countersuit for defamation against seven women who previously accused him of sexual misconduct. After the suit was filed, Pressley said in a statement that the women have made "malicious, opportunistic and false and defamatory" comments about him.

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