CEDAR RAPIDS, Iowa (AP) — Former Vice President Mike Pence declared Wednesday he will challenge a subpoena by the special counsel overseeing Trump investigations — pursuing it to the Supreme Court if necessary.

Special counsel Jack Smith, appointed by the Justice Department, is investigating efforts by former President Donald Trump and his allies to overturn the results of the 2020 election. Pence was at the Capitol for the ratification of Joe Biden’s victory as Trump supporters attacked the building on Jan. 6, 2021.

Smith is trying to compel Pence’s testimony before a grand jury.

“Let me first be clear: I’m going to fight the Biden DOJ subpoena for me to appear before the grand jury because I believe it’s unconstitutional and it’s unprecedented,” Pence told reporters in Iowa, the state that will hold the first nominating contest of the GOP primary.

“Never before in American history has a vice president been summoned to appear in court to testify against the president with whom they serve,” he said.

He said he was prepared to take the case “as far as it needs to go, if needs be to the Supreme Court of the United States.”

The Associated Press previously reported that Pence, who has been laying the groundwork for a likely presidential run in 2024, was ready to contest the demand for his appearance on constitutional grounds.

Aides argue that because he was serving in his role as president of the Senate on Jan. 6, he is protected under the Constitution’s “speech or debate” clause from being forced to testify. That provision is intended to protect members of Congress from questioning about official legislative acts.

A spokesman for Smith declined to comment. The Justice Department, which had earlier declined to comment on Pence’s subpoena, is expected to oppose the former vice president’s efforts and make the case that his cooperation is essential.

Pence noted during an earlier stop in Minneapolis that he has written and spoken extensively about Trump’s efforts to pressure him to overturn the results of the election — something he did not have power to do — and has repeatedly denounced Trump’s efforts as “reckless” and “dangerous.”

“I have nothing to hide and I’m proud of what we accomplished. But for me, this is a moment where you have to decide where you stand, and I stand on the Constitution of the United States,” he said.

He added that he expects Trump to try to assert executive privilege to block his own testimony. “That’s not my fight. My fight is on the separation of powers,” Pence said.

Pence made his remarks after headlining events in Minneapolis and Cedar Rapids aimed at rallying conservative parents opposed to transgender-affirming policies in public schools. The events came as a federal appeals court was due to hear oral arguments in St. Paul in a lawsuit brought last summer by a group representing parents of students in Linn-Mar Community School District in Marion, Iowa.

Parents Defending Education is trying to overturn a policy adopted by the school board last year allowing transgender students to request a gender support plan to begin socially transitioning at school without the permission of their parents. Pence’s advocacy group, Advancing American Freedom, has filed an amicus brief in the case, as have dozens of mostly conservative groups and several conservative states.

“Across the country, parents’ rights are being trampled by a politically correct nanny state that’s ruining our schools and telling our parents that they have no role in their children’s most important decisions,” Pence said in Minneapolis, where he argued that parents must be informed of such decisions. “You do not craft a gender transition plan for my child without my knowledge or consent,” he said.

Though Pence says he has yet to make a decision about 2024, he has visited leadoff Iowa several times since the 2020 election. And his Wednesday event had the look of a campaign stop, held in a pizza store where candidates commonly hold court with voters.

Pence is hoping to draw the support of social and religious conservatives in what could be a crowded primary contest that already includes Trump and former United Nations Ambassador Nikki Haley, who formally launched her campaign Wednesday.

To that end, Pence’s advocacy group launched a new campaign last week on the schools issue, a flashpoint for many on the right, as Haley and other presidential prospects, including South Carolina Sen. Tim Scott, prepare for their own visits to the state this month.

___ Associated Press writer Steve Karnowski in Minneapolis contributed to this report.

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