A legal fight has erupted over a Washington, D.C., police officer who was communicating with Proud Boys leader Enrique Tarrio in the run-up to the Jan. 6, 2021, Capitol attack that could shape the outcome of the upcoming trial of Tarrio and other far-right extremists.

Metropolitan Police Lt. Shane Lamond's testimony is crucial for the former Proud Boys national chairman's defense against seditious conspiracy and other serious charges stemming from the attack, Tarrio's attorneys say.

But Lamond plans to invoke his Fifth Amendment privilege against self-incrimination if called to the witness stand after prosecutors warned the officer he could be charged with obstructing the investigation into Tarrio, the Proud Boy's attorneys say. They have accused the Justice Department of trying to bully Lamond into keeping quiet because his testimony would hurt their case. Prosecutors have vehemently denied that charge.

The legal skirmish is unfolding two weeks before jury selection is supposed to begin in one of the highest-profile cases the Justice Department has brought since the Jan. 6 insurrection. Prosecutors charge Tarrio and four co-defendants conspired to forcibly stop the transfer of presidential power from former President Donald Trump to Democrat Joe Biden.

The Proud Boys trial will be another major test for the Justice Department, which secured a major victory last month in the seditious conspiracy convictions of two other far-right extremist group leaders: Oath Keepers founder Stewart Rhodes, of Granbury, Texas, and Kelly Meggs, who was the leader of the group's Florida chapter. Tarrio's far-right, male chauvinist extremist group that seized on the Trump administration's policies was a major agitator during earlier pro-Trump protests and at the Capitol on Jan. 6.

Tarrio wasn't in Washington when the riot erupted, but authorities say he helped put into motion the violence of that day. Shortly before the riot, authorities say Tarrio posted on social media that the group planned to turn out in "record numbers" on Jan. 6, but would be "incognito" instead of donning their traditional clothing colors of black and yellow.

Tarrio was arrested in Washington two days before the riot and charged with vandalizing a Black Lives Matter banner at a historic Black church during a protest in December 2020. Tarrio was released from jail on Jan. 14, 2022 after serving his five-month sentence for that case.

Tarrio's lawyers say Lamond has been under investigation for some time for possible obstruction of justice into the investigation of the Proud Boys leader.

Lamond was placed on administrative leave by the police force in February, said Mark Schamel, an attorney for the officer. Schamel said Lamond is a "decorated veteran" of the D.C. police department and "doesn't share any of the indefensible positions" of extremist groups.

Lamond, an intelligence officer for the police force, was responsible for monitoring groups like the Proud Boys when they came to Washington. Tarrio regularly communicated with Lamond before the Proud Boys came to the capital city to discuss the "purpose of the trip, the agenda, and the location," defense lawyers wrote in court documents.

Tarrio told Lamond that Proud Boys would not be wearing their traditional colors of black and yellow in order to protect themselves from possible attacks from antifa activists. Tarrio told the officer they planned to watch Trump's speech, protest the results of the election "and later that night they planned to party with plenty of beers and babes," Tarrio's lawyers wrote.

"He told me they are trying to go incognito this time," Lamond told fellow officers in one message, according to Tarrio's attorneys. "Even if they aren't wearing their colors they will stick together as a group so we should be able to identify them. Not to mention they won't be head to toe in black with makeshift shields!"

The defense says Lamond's testimony would support Tarrio's claims that he was looking to avoid violence, not cause it. Tarrio's lawyers have asked the judge to dismiss the case if the government refuses to grant immunity for Lamond so he can take the stand.

"How can there be sedition if the Proud Boys are informing law enforcement of their plans on Jan. 6?" Tarrio attorney Sabino Jauregui said during a recent hearing. "They don't want him to testify because it will completely destroy their case."

Assistant U.S. Attorney Erik Kenerson told the judge the suggestion that prosecutors are pressuring and threatening witnesses is "categorically false."

Tarrio has a history of cooperating with law enforcement.

Court records uncovered last year showed that Tarrio previously worked undercover and cooperated with investigators after he was accused of fraud in 2012. After Tarrio's indictment for participating in a scheme involving the resale of diabetic test strips, he helped the government prosecute more than a dozen other people, according to court papers.

Tarrio will stand trial with four others: Ethan Nordean, of Auburn, Washington; Joseph Biggs, of Ormond Beach, Florida; Zachary Rehl, of Philadelphia and Dominic Pezzola of Rochester, New York.

Alanna Durkin Richer reports for the Associated Press.

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