The Trump supporter is the only one of the 16 fake Michigan electors who has agreed to cooperate with the authorities and had charges against him dropped.One of the Republicans in Michigan who acted as a fake elector for Donald J. Trump expressed deep regret about his participation, according to a recording of his interview with the state attorney general’s office that was obtained by The New York Times.The elector, James Renner, is thus far the only Trump elector who has reached an agreement with the office of Michigan Attorney General Dana Nessel, which brought criminal charges in July against all 16 of the state’s fake Trump electors. In October, Ms. Nessel’s office dropped all charges against Mr. Renner after he agreed to cooperate.Mr. Renner, 77, was a late substitution to the roster of electors in December 2020 after two others dropped out. He told the attorney general’s office that he later realized, after reviewing testimony from the House investigation of the Jan. 6, 2021, attack on the Capitol, that he and other electors had acted improperly.“I can’t overemphasize how once I read the information in the J6 transcripts how upset I was that the legitimate process had not been followed,” he said in the interview. “I felt that I had been walked into a situation that I shouldn’t have ever been involved in.”Mr. Renner’s lawyer, Matthew G. Borgula, had no comment.Charges have now been brought against fake electors in three states — Georgia, Michigan and Nevada — and investigations are underway in other states, including Arizona and New Mexico. In Georgia, prosecutors in Fulton County, which includes Atlanta, have looked far beyond the electors themselves and charged Mr. Trump, the former president, and many of his key allies over their efforts to keep him in power despite his loss in 2020. Mr. Trump also faces charges over election interference from Jack Smith, the special counsel appointed by U.S. Attorney General Merrick Garland.In Michigan, Ms. Nessel, a Democrat, has only charged the electors, but has said her investigation is still open. During their interview of Mr. Renner, her investigators asked about a number of other people involved, including Shawn Flynn, a lawyer who worked with the Trump campaign on the ground in Michigan, and Rudolph W. Giuliani, Mr. Trump’s former personal lawyer. (Mr. Giuliani is among those charged in Georgia; both he and Mr. Trump have pleaded not guilty.)It is not clear if they, or Mr. Trump himself, have legal exposure in Michigan. The Detroit News recently reported that Mr. Trump was taped in December 2020 pressuring two members of the Wayne County Board of Canvassers not to certify the election results, providing direct evidence of his role in trying to overturn the Michigan vote.Mr. Renner is a former state trooper and a retired businessman who volunteered as a local party activist in Clinton County, which is near Lansing, the state capital. He had never served as an elector before and typically supported Republican campaigns by passing out signs and distributing fliers. He said he was contacted by the head of the county Republican Party a day or so before the electors had planned to meet on Dec. 14, 2020, was asked to fill in for someone who was dropping out and agreed to do so.Attorney General Dana Nessel of Michigan brought criminal charges against all 16 of the state’s fake Trump electors in July.Nick Hagen for The New York TimesSince Michigan had already been certified for Joseph R. Biden, Jr., who won the state by more than 150,000 votes, the Trump electors were barred from convening in the Capitol building, which was largely closed at the time because of the pandemic. They ended up meeting in the basement of the state Republican headquarters.During a pretrial hearing earlier this month for several of the electors, Laura Cox, the former chairwoman of the state Republican Party, testified that she and other local party officials had drafted language for the electors to sign that made clear they were only acting on a contingency basis, in the event that the Trump campaign’s election litigation succeeded. But Ms. Cox was sidelined by Covid on the day of the meeting, and she said the Trump campaign went against her instructions by not including such language.At the same pretrial hearing, Terri Lynn Land, a former Michigan secretary of state who was originally designated as a 2020 Republican elector, said she declined to meet on Dec. 14, 2020, because Mr. Trump had not been certified by state officials. Tony Zammit, a former spokesman for the state party who attended part of the meeting, testified that in his view, the “vast majority” of the electors were not culpable but “going along with what the lawyers were telling them.”Mr. Renner said in his interview with investigators that when he showed up, “I knew nothing about the electoral process.” Three of the electors took the lead at the signing session, he said: Meshawn Maddock, a former co-chair of the state Republican Party; Kathleen Berden, a Republican national committeewoman; and Marya Rodriguez, the only lawyer among the electors. (They have all pleaded not guilty.)In the interview, Mr. Renner said that “I was accepting the individuals that were in authority” knew “what they were talking about.”But he said that he later began studying the House transcripts and official procedure for the electors after he and the other fake Trump electors were sued in civil court this January. And he was alarmed by what he found, he said.“It was only then that I realized that, hold it, there is an official state authorized process for this,” he said. Before that, he said, “I had never been an elector, I had never discussed it with anybody. I was used to a much more informal process at the county level. And so that’s when I became suspicious of what had gone on.”He said he later realized that “what happened was not legitimate.”In Georgia, more than half of the fake Trump electors agreed to cooperate with prosecutors before charges were brought in the case there. In Michigan, all eight charges against Mr. Renner, including forgery and conspiracy counts, were dropped as part of his agreement with Ms. Nessel’s office.Her ongoing investigation means that the legal aftermath of the last presidential election in Michigan will not be over before voting begins in the next one. Pretrial hearings in the electors case are scheduled to last into February; the state’s presidential primary takes place on Feb. 27.“I am very upset, I don’t show it, but I am,” Mr. Renner told investigators, adding that to say he felt “betrayed is an understatement. That’s all I can say.” More