The motion was made public Wednesday but submitted Tuesday, the day the 20-year-old woman who accused the NBA star of sexual assault filed a civil lawsuit seeking monetary damages from him.
In a court filing, prosecutor Dana Easter said the release of the hearing transcript detailing a defense expert's testimony about the accuser's sexual activities was "extremely harmful" to the prosecution's case. She said a strict gag order issued by District Judge Terry Ruckriegle has prevented the prosecution from responding.
There has been "an absence of balance in the information released," Easter wrote. "The release of this information 28 days prior to trial will have the effect of tainting the jury pool and impact the ability of the prosecution to obtain a fair jury at this time."
The defense testimony from the closed hearing that was accidentally released including that of an expert who indicated that the accuser had sex with someone else after her encounter with Bryant but before she was examined at a hospital.
There was no immediate indication whether the judge would hold a hearing on the prosecution motion or when he might rule. Jury selection is scheduled to begin Aug. 27.
Defense attorney Pamela Mackey did not return a call, nor did the accuser's attorneys. Prosecution spokeswoman Krista Flannigan refused to comment further, saying the filing spoke for itself.
Bryant 25, has pleaded not guilty to felony sexual assault. He has said he had consensual sex with the woman, then 19, at the Vail-area resort where she worked last summer. The Los Angeles Lakers star faces four years to life in prison or 20 years to life on probation, and a fine of up to $750,000 if convicted.
The prosecution filing does not mention the civil suit filed in federal court in Denver, which seeks compensatory damages of at least $75,000, with punitive damages to be determined later.
Legal experts said the suit will hurt prosecutors because the defense can argue that the woman is trying for a financial award in a separate proceeding.
"Now it's up to the defense," says CBSNews.com Legal Analyst Andrew Cohen. "If Bryant's attorneys agree that a delay makes sense it will make it that much more likely that the judge will grant a continuance. But if they say they are ready to go and want a trial now it will be hard for the judge to agree to a delay.
"This is another sign that makes it less likely that Bryant won't go to trial at the end of August," says Cohen. "If the judge denies this motion -- and there is a decent chance of that -- then prosecutors can say with a straight face that they tried to achieve some form of justice but couldn't. In other words, they can blame the judge and then dismiss the charge."
"Now all of a sudden it looks like this whole thing was for money. If it's otherwise, then why would she file a civil case?" said Dan Recht, former president of the Colorado Criminal Bar Association. "In my mind, they would never file a civil case without having a strategy of getting the criminal case dismissed."
Attorneys John Clune and Lin Wood said their client was owed money for pain, "public scorn, hatred and ridicule" she has suffered as a result of the alleged attack last summer. They also accused Bryant of similar misconduct involving other women, but provided no details.
To win a civil lawsuit, a plaintiff must prove only that it is more likely than not harm was caused by the defendant. Prosecutors in a criminal case have to convince jurors beyond a reasonable doubt a defendant committed a crime, a much higher standard of proof.