• Special counsel Jack Smith urged a federal appeals court to reverse the dismissal of the criminal classified documents case against former President Donald Trump.
• U.S. District Judge Aileen Cannon in a stunning move threw out that case against Trump on the grounds that Smith's appointment violated the U.S. Constitution.
• Trump was charged with illegally retaining hundreds of highly sensitive classified records at his Mar-a-Lago resort home after leaving the White House.

Special counsel Jack Smith on Monday urged a federal appeals court to reverse a lower court's decision to dismiss the criminal case charging former President Donald Trump with mishandling classified documents.

U.S. District Judge Aileen Cannon in a stunning move in mid-July threw out that case on the grounds that Smith's appointment violated the U.S. Constitution.

Smith in Monday's court brief argued that Cannon's ruling strayed from binding legal precedent, "misconstrued" the laws authorizing the appointment of special counsels and "took inadequate account" of the history of those appointments.

Cannon's ruling "conflicts with an otherwise unbroken course of decisions, including by the Supreme Court," that the U.S. attorney general is empowered to appoint special counsels, Smith wrote in the filing in the U.S. Court of Appeals for the 11th Circuit.

"This Court should reverse," Smith wrote.

He also asked for the case to be remanded to the U.S. District Court in southern Florida. But he did not ask the appeals court to remove Cannon, a Trump appointee, from the case.

Lawyers for Trump, who is the Republican presidential nominee against Democratic Vice President Kamala Harris, did not immediately respond to CNBC's request for comment on Smith's brief.

Even if the appeals court grants Smith's request to reverse Cannon's decision, there is virtually no chance that Trump would face trial on the charges until well after the Nov. 5 presidential election.

Before she dismissed the case, a growing chorus of legal critics and others had accused Cannon of needlessly slow-walking the pretrial proceedings.

A federal grand jury had charged Trump with illegally retaining hundreds of highly sensitive classified records at his Mar-a-Lago resort home after he left the White House in January 2021, then trying to obstruct the government's efforts to get them back.

Smith's Monday afternoon brief pointed out that the Supreme Court, in its landmark 1974 decision United States v. Nixon, determined that the attorney general had authority to appoint a special prosecutor.

That determination has been upheld by every other court to consider the question — except for Cannon's, the special counsel wrote.

Smith's filing also argued that the logic of Cannon's ruling "needlessly casts doubt" on longstanding DOJ practices, and that it would suddenly call into question the validity of hundreds of appointments across the executive branch.

"The implausibility of that outcome underscores why the district court's novel conclusions lack merit," Smith wrote.