Homeland Security investigators conducted a wide-ranging surveillance campaign against Minnesota labor unions, trying to find evidence that they were part of an Antifa conspiracy to finance domestic terrorism, according to federal records provided to a group of protesters federally charged with impeding immigration enforcement officers during Operation Metro Surge.

Defense lawyers for the group that’s dubbed itself the Minnesota 15 have received some, but not all, government evidence related to the case. The documents confirmed that the government prosecutor who convened the grand jury to obtain the indictments was Deputy Attorney General Brian Lynch, a high-ranking Justice Department official who attended the Jan. 6, 2021 protests at the U.S. Capitol.

Lynch was appointed this year to be co-director of the Joint Task Force Vanguard, a special unit dedicated to prosecuting left-wing political violence.

Lynch was reportedly photographed participating in the Capitol protest, standing inside a restricted zone, while rioters stormed the building. The Justice Department did not respond to a request for comment from the Minnesota Star Tribune about Lynch’s involvement at the protest, but an official told Talking Points Memo last month that while Lynch was present at Jan. 6, he “never entered the Capitol, left the grounds after a brief period, and did not commit and was never accused of any violation of law.”

Kevin Riach, the lawyer for lead defendant Issac Sant, revealed the discovery materials in a court motion Thursday in which he demanded additional disclosures and indicated he intended to file a motion to dismiss for “selective prosecution.”

The Trump administration vacated or commuted the sentences of numerous individuals convicted of their actions related to Jan. 6, Riach argued, while prosecuting Minnesotans who protested ICE.

“The government’s initial disclosures chronicle [Homeland Security Investigations’] abuses and confirm the political animus driving this case,” the lawyer wrote, saying federal agents were “fueled by visions of this vast and irrational conspiracy.”

As part of the grand jury presentation in the case of the Minnesota 15 protesters, the Justice Department displayed a diagram arguing that several major labor unions were connected in “the Conspiracy” at the core of the case.

The unions, which traditionally align with Democratic political candidates, include the AFL-CIO, Minneapolis Federation of Educators, Minnesota Association of Professional Employees and the Service Employees International Union.

Homeland Security investigators secretly obtained financial records of the labor unions and nonprofit organizations listed in the diagram, and also sought records regarding the Communications Workers of America, which represents most of the nation’s unionized journalists, including the Star Tribune.

Marcia Howard, Teacher Chapter president of the Minneapolis Federation of Educators, Local 59, dismissed the Homeland Security investigation into her union as “politically motivated.”

“Minneapolis educators worked in union to exercise our constitutional rights to peacefully protest Operation Metro Surge and other discriminatory policies of the president — and we will continue to do so,” Howard said in a statement. “For now, we have no further comment about this so-called investigation into whatever they’re calling ‘Antifa’ today.”

The Minnesota AFL-CIO called the Justice Department’s Antifa conspiracy theory in the Minnesota 15 case “unhinged.”

According to Riach’s motion, undercover Homeland Security agents infiltrated in-person meetings of the groups they were surveilling, actively participating in organizing while trying to entice activists into committing crimes. One investigative report described how an undercover agent attending a meeting of the climate action group Sunrise Movement offered his construction skills to help build items for more “direct-action” protests after learning the group focused on “peaceful” protests.

Also included in the government’s “conspiracy” web was Monarca, the rapid response arm of the pro-immigration nonprofit Unidos MN, which trained tens of thousands of people from Minnesota and surrounding states during Operation Metro Surge to be “constitutional observers” of ICE. Monarca provided guidance on distinguishing judicial warrants from administrative warrants, nonviolent tactics like using whistles to alert the presence of ICE agents and filming immigration enforcement officers in public without interfering.

Monarca suspected they were being investigated during Metro Surge because the government has done it before — such as during the McCarthy era, said executive director Emilia Gonzalez Avalos.

“I am glad that we still have some institutional guardrails where this information can now be revealed to the public,” she told the Star Tribune. “Because Americans should know that their government is spying on us for their own personal motives.”

The U.S. Attorney’s Office, which is expected to respond to the motion in court, declined to comment on Wednesday.

susan.du@startribune.com