Bill Cosby is now in state prison, convicted of assaulting Andrea Constand in 2004. But Constand's defamation lawsuit will continue against a former Pennsylvania prosecutor who chose not to charge Cosby in 2005.

A federal judge in Philadelphia on Tuesday denied a summary judgment motion by former Montgomery County District Attorney Bruce Castor Jr., allowing the case to proceed. Constand alleges that Castor depicted her as a liar in statements he made three years ago.

Constand brought the defamation suit in October 2015, about two months before Cosby was criminally charged in Montgomery County based on assault allegations she brought a decade before, as well as additional evidence that became public in 2015. Cosby was found guilty of aggravated indecent assault in April and sentenced to three to 10 years in state prison.

In a lengthy footnote to Tuesday's order, U.S. District Senior Judge Eduardo Robreno of the Eastern District of Pennsylvania explained that two public statements Castor made, years after choosing not to charge Cosby with a crime, could be seen as defamatory.

In a 2015 statement to The Associated Press, Castor suggested Constand's claims in a later civil suit against Cosby went beyond her initial description of Cosby's conduct. ”If the allegations in the civil complaint were contained with that detail in her statement to the police, we might have been able to make a case out of it,” Castor told the AP at the time.

“The average reader could interpret defendant's statement alongside his decision not to prosecute Mr. Cosby to mean plaintiff lied, possibly for pecuniary gain. The implication that plaintiff lied in her civil complaint is capable of defamatory meaning,” Robreno wrote.

And even if that statement reflected an opinion, Robreno said, Castor did not offer reasoning to back up his opinion, and it could have been based on undisclosed information he knew from his time as a prosecutor.

The order also pointed to a tweet Castor posted in September 2015: “'Inky: Cosby victim told police much different than she told court in her lawsuit. First I saw that in a story. Troublesome for the good guys. Not good.'”

Robreno said Castor's argument that the tweet was literally true, or an opinion, was not convincing enough to grant summary judgment.

Castor filed his own suit against Constand and her lawyers in October 2017 in the Philadelphia Court of Common Pleas, alleging that she only brought her defamation claim in order to ruin Castor's chances in a 2015 election for district attorney. The suit was dismissed in April, based on preliminary objections, but Castor is appealing to the Pennsylvania Superior Court.

In an opinion filed Sept. 20, Philadelphia Court of Common Pleas Judge Ann Butchart said Castor's second amended complaint “after three attempts … was unable to conform” with Pennsylvania's Rules of Civil Procedure. She said his complaint failed to state a claim for abuse of process while containing “scandalous and impertinent matters.”

Justin Bayer of Kane, Pugh, Knoell, Troy & Kramer in Norristown, who is representing Castor, did not immediately return a call seeking comment Thursday.

Bebe Kivitz, one of Constand's lawyers, also did not return a call for comment.

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