Attorneys for three of the four former Minneapolis police officers charged in George Floyd's death are asking a judge to dismiss the cases against their clients because of alleged misconduct and intentional sabotage by prosecutors.

J. Alexander Kueng's attorney, Thomas Plunkett, filed a motion late Tuesday accusing Attorney General Keith Ellison's office of mishandling how it shared evidence with defense attorneys — a process known as "discovery" — and of leaking information about reported plea negotiations with co-defendant Derek Chauvin, who planted his knee on Floyd's neck for more than nine minutes.

"The history of this case shows purposeful actions to thwart justice for the officers," Plunkett wrote. "One discovery violation is an honest mistake, this wide river of flagrant discovery violations is a purposeful act designed to prevent Mr. Kueng and [the co-defendants] from receiving a fair trial. Leaking prejudicial information mere days before a trial is loathsome and underhanded.

"The state's conduct has been pervasive, malicious and an affront to the dignity of the office of the Attorney General."

In a motion filed Monday, attorneys Robert and Natalie Paule, who represent Tou Thao, first accused Ellison's office of leaking the plea negotiation, and asked for a dismissal of the case against their client. Attorney Earl Gray, who represents Thomas Lane, filed a motion Wednesday asking to join Thao's and Kueng's motions.

Ellison denied the accusations.

"It's sad that the defense would stoop to peddling baseless conspiracy theories rather than prepare a serious defense of their client to address the grave crimes with which he is charged," Ellison said in a written statement.

"Unlike the defense, we are confident in our case and look forward to presenting it to a jury."

Joseph Daly, emeritus professor at Mitchell Hamline School of Law, reviewed the motions and said such accusations are uncommon.

"I find it to be rather shocking," Daly said. "I've never seen a criminal case where such strong language has been used against opponent lawyers. The case is really supposed to be the state of Minnesota against these individual defendants. It's not supposed to be the lawyers versus the other lawyers."

Chauvin's attorney, Eric Nelson, filed a motion in December and an affidavit in January expressing his "absolute anger and frustration" with how prosecutors handled discovery, but has not weighed in on the leak of the reported plea deal.

Nelson was not representing Chauvin at the time of the reported negotiations. Chauvin is scheduled to be tried March 8 on charges of second-degree murder and manslaughter.

Plunkett deferred to his motion when reached by phone Wednesday, the same day the filing was made public.

Plunkett's accusations revisited discovery issues that first surfaced in December in motions filed by Thao's and Chauvin's attorneys.

They piggybacked on Thao's motion Monday, which accused Ellison's office of leaking information attributed to anonymous law enforcement officials in New York Times and Associated Press articles that reported Chauvin was ready to plead guilty to third-degree murder last year until the deal was rejected by then-U.S. Attorney General William Barr.

Plunkett adopted the statements in the discovery and Thao motions, and in Nelson's January affidavit. He asked for an in-person hearing to solicit testimony from attorneys on the issues, a finding that Ellison's office committed prosecutorial misconduct, and referral of the case to the Minnesota Lawyer's Professional Responsibility Board for further investigation.

Plunkett also asked for a judge's order requiring Ellison's office to compensate defense attorneys for "time spent sifting through and organizing" what he described as "discovery soup," among other requests.

Attorneys for all four defendants have accused prosecutors of burying important information between irrelevant material, providing duplicates of the same item, turning over thousands of pages of unrelated documents and missing deadlines.

Ellison's office has denied the allegations, saying they provided information as they received it from Minneapolis police and the Minnesota Bureau of Criminal Apprehension (BCA), which investigated the case.

Hennepin County District Judge Peter Cahill ruled Jan. 11 that while prosecutors shared one document late, they acted in good faith overall. Nelson filed an affidavit Jan. 26 renewing his concerns about discovery after obtaining copies of the same evidence from the BCA.

Plunkett also criticized Ellison for missing a Jan. 7 hearing in the case despite an e-mail from Assistant Attorney General Matthew Frank noting that he would attend.

"Mr. Ellison's late decision to absence himself from the hearing suggests he knew about and may have been personally involved in developing the strategy to cheat the defendants out of their rights to due process," Plunkett wrote.

"Mr. Ellison distanced himself and did nothing to intervene or correct the course of the state's ill-intentioned ship."

Daly and veteran attorney Doug Kelley said Kueng's and Thao's motions didn't provide evidence to support the allegations about the Chauvin leak. Neither motion included affidavits — statements made under oath providing evidence to back claims.

Thao's attorneys wrote that, "Using deductive reasoning, the leak had to have come from the state."

"The defense had the right to bring a motion based on the newspaper story, and I think they brought the motion in good faith," Kelley said. "The trouble is I just don't think they have the evidence."

The Hennepin County Attorney's Office charged and handled Chauvin's case alone at first, but Ellison's office soon took over with assistance from the county.

The leak could have come from several places, Kelley said, including the county attorney's office, Ellison's office, the U.S. Attorney's Office, Minneapolis police or the BCA, among others.

Daly said raising the issue now could be helpful if the defendants are convicted, because in an appeal it could be used to argue that the leak caused jurors to find their clients guilty through association given Chauvin's reported willingness to admit to the crime.

Raising the issue after a conviction would weaken the argument, Daly said.

Kueng, Thao and Lane are charged with aiding and abetting second-degree murder and manslaughter in Floyd's death on May 25 and are scheduled to be tried in one trial Aug. 23. All four defendants, who were fired, are out on bond.

"Lawyers are always careful to bring up the objection when it occurs," Daly said. "They don't want to wait until afterward in case the court says, 'You should have brought it up sooner.' "

Chao Xiong • 612-270-4708

Twitter: @ChaoStrib