The Philadelphia District Attorney’s Office on Thursday filed a highly unusual set of documents in a murder case, accusing two homicide detectives of illegally searching the defendant’s cell phone, and suggesting that the defense attorney — whose firm also represents members of the police union — had asked prosecutors to let his client plead guilty in order to keep the detectives' alleged conduct from the public.

The set of motions asks Common Pleas Court Judge Barbara A. McDermott to disqualify attorney Bill Davis, claiming that he discovered video evidence that would prove the detectives performed the illegal search, but told a supervisor in the District Attorney’s Office he did not want it to become public because “I don’t want to end anyone’s career." The motions allege that Davis' behavior resulted from his firm’s representation of police officers accused of misconduct.

The documents also allege that the supervisor — whom Davis identified as Anthony Voci, the chief of homicide cases — told Davis that “perjury charges were possible” against the detectives, Freddie Mole and Joseph Murray. And they say prosecutors do not think either officer would be able to testify in the case without invoking the Fifth Amendment right against self-incrimination.

On Thursday night, Davis denied the allegations against him, saying it “is completely false and ludicrous” to suggest that he has a conflict of interest simply because his firm, McMonagle, Perri, McHugh, Mischak & Davis, has a contract with the Fraternal Order of Police lodge. He said he had been advocating vigorously for the defendant, Marquise Noel.

Davis said it was he who recovered the evidence of the detectives looking at a cell phone without a search warrant while in a hospital trauma bay — and it was he who brought the evidence to Voci’s attention. He said he sought to use it to get a favorable resolution for Noel, 21, of Eastwick, who has pleaded not guilty but faces the possibility of life in prison without parole.

“I made the mistake during the conversation with the chief of homicide, Voci, of showing some humanity” toward police detectives he’s known for years, Davis said. "I did tell him [Voci] on a personal note that I’ve known the assigned detectives, and I would love to avoid ending their careers and really hurting their families, if possible.“

Davis said he told Voci that he realized Voci might have to reveal the video evidence to his supervisors.

The episode represents an unusually pointed and public accusation from a prosecutor’s office that in its first year under Larry Krasner, a former criminal defense attorney, has clashed with police and charged officers with wrongdoing in ways Krasner’s predecessors had not.

Attempts to reach Mole for comment Thursday night were unsuccessful. Murray declined to comment.

Commissioner Richard Ross said Thursday night that he had not read the district attorney’s motion or seen the video, but that the allegations against the detectives were under Internal Affairs investigation.

Davis and prosecutors are scheduled to argue a defense motion to suppress the cell-phone evidence Friday morning at the Criminal Justice Center. Now, given the prosecutors’ filings, they likely will discuss the new motions as well.

The case involves a homicide Feb. 11 in Eastwick. Noel is accused of fatally shooting Tafari Lawrence, 23, of Upper Darby, at 75th Street and Elmwood Avenue. According to the motions filed by prosecutors, information discovered on Noel’s black LG cell phone was key to solving the case.

The motions filed Thursday claim that several hours before Murray requested a search warrant for the device, Mole and Murray were captured on surveillance video examining “a black flip phone," which prosecutors believe was Noel’s, according to District Attorney’s Office spokesperson Ben Waxman. Davis said that although authorities contend the cell phone was Noel’s, he has seen no evidence to prove that.

The motions also say that Mole was asked twice at Noel’s preliminary hearing April 3 whether he reviewed the phone, and that both times he testified that he did so after receiving a search warrant.

The detectives' alleged conduct could jeopardize prosecutors’ ability to build a winnable case, the new motions allege.

And they say that Davis was not using that information to Noel’s advantage and therefore compromised Noel’s interests in favor of the police.

“This request for a plea bargain under these circumstances, which would place [Noel] in prison for years so that the officers depicted would not be embarrassed or have their careers ‘end[ed],’ illustrates that [Noel’s] interests have diverged from the interests of Mr. Davis’ firm’s future clients,” says the motion. “There is an actual conflict, and it has affected Mr. Davis' performance.”

Davis said that was not true.

He said that he called Voci on Wednesday afternoon to tell him of the video, and that Voci suggested he might be able to offer to let Noel plead guilty to third-degree murder with a sentence in the mitigated range, which Davis understood to mean 6½ to 13 years. Davis said he then suggested a deal with a five- to 10-year sentence.

In a subsequent phone conversation Wednesday, Davis said, Voci again pressed to see the video. Davis told Voci he would only be willing to send the video if the District Attorney’s Office would offer his client the lower sentence. He ultimately sent the video believing that Voci would be willing to do so. Davis said he had not yet discussed any possible deal with Noel.

Voci “said if it showed what I said it showed, we could work something out,” said Davis.

Davis said he did not hear back from the District Attorney’s Office until 3 p.m. Thursday, when he was notified of its new motions seeking to disqualify him.

He said that although his firm represents the FOP to defend police officers, it does so on a case-by-case basis. In the past, he said, his firm has not represented police officers accused of lying, and it avoids cases with any potential conflict of interest.