Bill Cosby’s defense team is asking a judge to seal the transcript of a 2005 deposition in which Cosby admits to buying a powerful sedative to give to women with whom he wants to have sex. (Jenny Starrs/The Washington Post)

Of all the delicate, high-stakes maneuvering in the multi-state Bill Cosby legal saga, one of the strangest is playing out in a federal court in Massachusetts.

Cosby’s defense team is asking a federal magistrate judge to place under seal the 900-page transcript of a deposition given by the comedian in which he admits to buying Quaaludes, a powerful sedative, to give to women with whom he wants to have sex. What makes the request notable is that the transcript, far from being a secret court document, is already in the possession of several news organizations, including The Washington Post, the New York Times and the Associated Press, all of which bought it from a court stenography service and reported extensively on its contents last July.

Judge David H. Hennessy, the magistrate assigned to untangle the request, expressed a measure of bafflement at a hearing late last month, likening the efforts of Cosby’s attorneys to the nearly impossible task of putting “toothpaste back in the tube.”

But the request, and the ongoing efforts by Cosby’s team to seal the transcript, offers insights into the team’s legal strategy, as well as a window into the realities of an information-overloaded, short-attention-span media age. The details of the deposition may have already been reported, Cosby attorney Marshall Searcy said in a hearing, but if the judge declines to seal the deposition, the transcript would once again become a “news item” and enter “the news cycle.”

“Seeking to seal it here stops the further dissemination,” Searcy said.

Cosby gave the deposition over the course of four days in 2005 and 2006 during a civil lawsuit filed against him by Andrea Constand, a former Temple University basketball official who accused him of drugging and sexually assaulting her. The Constand case ended in a confidential settlement, and the deposition remained secret for a decade.

But it resurfaced last summer when it was unearthed by attorneys for Cosby accusers and by several news organizations. It has since come to play a pivotal, potentially defining role in two major cases involving Cosby: a criminal sexual assault prosecution of the comedian in Pennsylvania stemming from Constand’s allegations and a civil defamation lawsuit filed against him by seven of his accusers in Massachusetts, where he has his primary residence.

Cosby has said he didn’t sexually assault women and is fighting the criminal charge filed against him in December. His attorneys have said the comedian admitted in his deposition only to using Quaaludes for sex with willing partners and that there are “countless tales of celebrities, music stars, and wealthy socialites in the 1970s willingly using Quaaludes for recreational purposes and during consensual sex.”

In the criminal prosecution, the use of the deposition is a centerpiece of the Cosby defense team’s attempt to get the case dismissed. The 78-year-old comedian’s attorneys have asserted that Cosby agreed to be deposed only because the district attorney in Montgomery County, Pa., overseeing the case at the time had promised not to prosecute. The current district attorney has said no formal promise was made. The judge in Cosby’s criminal case refused to throw out the case, but the comedian’s attorneys have appealed his decision, stalling the criminal case while a higher court considers the appeal.

In the Massachusetts civil case, attorneys for seven Cosby accusers have sought to use the transcript of the deposition to buttress their claims that the comedian used drugs as a tool in his alleged sexual assaults.

After criticism from Cosby’s attorneys about the initial sales of the transcript, the court reporting service has stopped making the deposition available. The Cosby attorneys say that the judge would damage their client by making the transcript publicly available again.

“It’s not just a question of getting the toothpaste back in the tube, but stopping what’s now been a continuing, for lack of a better word, injury to the defendant, Mr. Cosby,” Searcy argued at the March hearing.

In an extended back-and-forth with the judge, Searcy acknowledged that the full deposition transcript is not under seal. The judge said that as long as no “misconduct” took place in the release of the transcript, restricting use of the material could be a violation of First Amendment free-speech protections. But he has yet to issue a decision.

One possible motivation for keeping the deposition transcript from being disseminated further would be to make sure it doesn’t “poison the jury pool,” Hennessy said. But, he added, that shouldn’t be a concern because the jury selection process is designed to determine whether potential jurors can be fair and impartial.

The fight over the deposition traces back to last year, when attorneys for the Associated Press asked a federal judge in Pennsylvania to unseal a cache of documents related to Constand’s 2005 civil case. At the time, Cosby was big news. In the previous months, dozens of women had publicly accused him of sexually assaulting them in alleged encounters that took place over four decades. (The total number of accusers now surpasses 50.)

The judge, Eduardo Robreno, granted the AP’s request and wrote a stinging opinion, noting “the stark contrast between Bill Cosby, the public moralist and Bill Cosby, the subject of serious allegations concerning improper (and perhaps criminal) conduct.”

The newly released documents, which included excerpts from Cosby’s 2005 deposition, contained a startling detail: Cosby had admitted in the deposition that he acquired Quaaludes to give to women with whom he wanted to have sex.

But that wasn’t the whole story. Less than two weeks later, news organizations — first the New York Times, and later the Associated Press and The Washington Post — bought copies of the full deposition from the court reporting service. That generated longer, much more detailed stories about Cosby’s behavior, including how he would ask talent agents to send him young, struggling models and actresses as dinner companions. At least one of those women has accused him of sexual assault.

Cosby’s attorneys were furious, and they have sought sanctions against Constand and her attorneys, suggesting that they violated the terms of their confidential settlement by allowing the full deposition transcript to be released by the court reporter they had hired for the 2005 deposition.

The court reporter, Gregg Wolfe, stated in an affidavit that he thought Robreno’s ruling made it acceptable for him to release the transcripts.

So far, no news organization has published the full transcript of the deposition, meaning other media outlets that want to delve into Cosby’s testimony must rely on existing published reports that refer to passages from the deposition but don’t provide a word-for-word account.

Cosby’s attorneys want to keep it that way.

Scott Higham contributed to this report.