After six years of litigation, former Neurology professor Tracy McIntosh's sentence for sexual assault is still up in the air.

The Philadelphia District Attorney's office and McIntosh's attorney both filed briefs earlier this month regarding McIntosh's appeal of his three-and-a-half to seven-year prison sentence for sexually assaulting his college roommate's niece in 2002.

McIntosh's court-ordered resentencing in February followed a lenient house-arrest sentence imposed in 2005.

He is now appealing the more-recent sentence, saying his plea of no contest was based on an understanding that he would not receive prison time in exchange for the plea.

McIntosh's lawyers wrote in the brief that the oral deal between the defense and prosecutors was binding and that Judge Rayford Means, the judge who imposed the house-arrest sentence, honored this agreement.

"This matter became ripe for litigating" when the court ordered Means to resentence, the brief said.

The district attorney's brief, however, said McIntosh's new sentence should be affirmed.

When McIntosh entered his plea in 2004, he did not dispute that the plea was open even when the prosecution appealed the sentence that allowed him to avoid incarceration, according to the prosecutors' brief.

The district attorney's office has said the plea did not include an agreement about sentencing.

"The defendant's claim is frivolous," the prosecution wrote.

McIntosh waived his claim to an undisclosed sentencing agreement when he repeatedly failed to bring it up over two years for litigation, prosecutors say.

Assistant District Attorney Richard DeSipio and Joel Trigiani, McIntosh's lawyer, did not return phone calls for comment.