Washington — Former President Donald Trump announced that he will attend arguments Tuesday before a three-judge panel in Washington that is considering whether he is shielded from federal criminal prosecution.

Oral arguments before the U.S. Court of Appeals for the District of Columbia Circuit will focus on Trump's legal theory that the charges — namely that he engaged in an alleged scheme to subvert the results of the 2020 presidential election — should be dismissed because the alleged conduct occurred when he was president.

A lower court has already ruled that Trump is not absolutely immune from prosecution, and the outcome of the appeal could potentially derail the charges brought by special counsel Jack Smith over Trump's actions surrounding the 2020 presidential election.

The case will be heard by Judges Karen LeCraft Henderson, Michelle Childs and Florence Pan. Last week, two sources with knowledge of Trump's plans told CBS News that he was expected to attend the arguments in D.C. on Tuesday. The former president confirmed his plan in a social media post early Monday morning, and claimed he was "looking for voter fraud" in the aftermath of the election. Smith, though, has argued he was engaging in illegal acts to remain in power despite losing at the ballot box.

Trump's attendance is not mandatory, though defendants have a right to be present for proceedings.

Trump's immunity claim

In written briefs filed ahead of Tuesday's hearing, the former president's legal team wrote that the four charges against Trump, to which he pleaded not guilty, are "unlawful and unconstitutional" because they target "official acts" Trump took as president. Trump's attorneys argued that because the alleged conduct described in Smith's indictment occurred while Trump was in office, the Constitution prescribes that he can only be criminally prosecuted if first convicted by the Senate following an impeachment trial. 

"Before any single prosecutor can ask a court to sit in judgment of the President's conduct, Congress must have approved of it by impeaching and convicting the President. That did not happen here, and so President Trump has absolute immunity," Trump's attorneys wrote, pointing to the 2021 impeachment of the former president by the House, after which he was acquitted by the Senate.  

The special counsel, however, rebutted those claims outright in a filing of his own. He warned that Trump's legal theory "threatens to license Presidents to commit crimes to remain in office."

Prosecutors argued that even if Trump had some level of immunity for official acts carried out in his role as president, "the indictment contains substantial allegations of a plot to overturn the election results that fall well outside the outer perimeter of official Presidential responsibilities." Smith's team also argued that Trump was charged with different crimes than those he faced during his impeachment trial, so no limitations tied to past congressional proceedings should be placed on his criminal trial.

The House impeached Trump on a single article charging him with "incitement of insurrection." He faces four different counts for his alleged conduct surrounding the 2020 election, including obstruction of an official proceeding and conspiracy to defraud the United States.

Tuesday's scheduled arguments come after U.S. District Court Judge Tanya Chutkan denied Trump's initial attempt to dismiss the case on grounds of presidential immunity. The judge found that the presidency "does not confer a lifelong 'get-out-of-jail-free' pass," and said Trump may be subject to "federal investigation, indictment, prosecution, conviction and punishment for any criminal acts undertaken while in office." 

Chutkan has set Trump's criminal trial for March 4, but the case is currently on hold as the immunity question is considered by higher courts.

In an attempt to expedite the proceedings, Smith's team asked the Supreme Court to grant an unusual request to take up the case before the appeals court considered it. But in an unsigned order, the high court last month opted not to take up the landmark case ahead of schedule. The decision does not preclude the losing party — either Trump or Smith — from seeking the Supreme Court's review again once the D.C. Circuit has ruled.

The jurisdiction question

Among the issues likely to be debated before the D.C. Circuit is whether the court even has jurisdiction over the appeal.

In a friend-of-the-court brief filed Dec. 29, American Oversight, a liberal watchdog group, argued that Trump could not ask the appeals court to review Chutkan's order denying presidential immunity. The group urged the D.C. Circuit to dismiss the appeal and send the case back to the district court for trial "without further delay."

Citing a unanimous 1989 Supreme Court decision authored by Justice Antonin Scalia, the group said an order denying immunity in a criminal case can only be appealed when the immunity claim "rests upon an explicit statutory or constitutional guarantee that trial will not occur." The high court has identified only two constitutional guarantees against trial that meet this standard, American Oversight argued: the double jeopardy clause and speech or debate clause, which shields members of Congress from being questioned about their legislative actions.

"Mr. Trump asserts immunity under structural constitutional principles and an unstated negative implication of the Impeachment Judgment Clause. Neither claim rests upon any explicit textual guarantee against trial," lawyers for the group told the D.C. Circuit in their filing.

Trump, they said, could return to the D.C. Circuit and press his presidential immunity claim after conviction, if he is found guilty on any of the four charges he faces.

In an unsigned order last week, the judges instructed lawyers for both sides to be prepared to address during oral arguments "any inquiries by the court regarding discrete issues raised" in friend-of-the-court briefs.

It's unclear how quickly the D.C. Circuit will issue a decision on the immunity matter, though it has acted swiftly in setting deadlines for filings and holding arguments. If the appeals court issues a decision on whether Trump is immune from federal prosecution, it can be appealed to the Supreme Court.

Fin Gomez and Olivia Rinaldi contributed to this report.

Robert Legare

Robert Legare is a CBS News multiplatform reporter and producer covering the Justice Department, federal courts and investigations. He was previously an associate producer for the "CBS Evening News with Norah O'Donnell."