A federal judge dismissed the classified documents case against former President Donald Trump on Monday, saying the appointment of special counsel Jack Smith was unconstitutional.

U.S. District Court Judge Aileen Cannon said Mr. Smith was a private citizen when Attorney General Merrick Garland plucked him to pursue cases against Mr. Trump. That violates the Constitution’s Appointments Clause, the judge ruled.

“Is there a statute in the United States Code that authorizes the appointment of Special Counsel Smith to conduct this prosecution? After careful study of this seminal issue, the answer is no,” wrote Judge Cannon, a Trump appointee.

She dismissed Mr. Smith’s case accusing Mr. Trump of mishandling classified documents by taking them from the White House and storing them at his Mar-a-Lago estate in Florida.

Her ruling can be appealed.

Judge Cannon delivered her ruling just hours before the Republican National Convention kicks off, and less than 48 hours after Mr. Trump survived an assassination attempt.

Mr. Trump, writing on Truth Social, hailed Monday’s ruling and said other cases against him should fall away, including a conviction in New York for business fraud and a civil sexual assault and defamation judgment.

“The Democrat Justice Department coordinated ALL of these Political Attacks, which are an Election Interference conspiracy against Joe Biden’s Political Opponent, ME,” he wrote.

Senate Majority Leader Charles E. Schumer, New York Democrat, called the ruling “breathtakingly misguided.”

“It is wrong on the law and must be appealed immediately,” he said, adding a call for Judge Cannon to be pulled from the case.

Questions about Mr. Smith’s appointment have swirled for months, raised in particular by conservative legal scholars who said Mr. Garland stretched the law by appointing him.

They said that the power to prosecute is a critical part of executive powers and those who bring cases must go through presidential nomination and Senate confirmation.

Mr. Garland defended the legality of picking Mr. Smith in testimony to Congress last month, saying that he thought he was following Justice Department policy.

“There are regulations under which the attorney general appoints special counsel. They’ve been in effect for 30 years, maybe longer under both parties,” he said. “The matter that you’re talking about, about whether somebody can have an employee of the Justice Department service special counsel has been adjudicated.”

Mr. Garland was referring to previous challenges to special counsels, including one that questioned the appointment of Robert Mueller to probe Mr. Trump while he was president.

In that case the U.S. Circuit Court of Appeals for the District of Columbia ruled that Mr. Mueller was “an inferior officer” who, under the law, did not need to have a presidential nomination or Senate confirmation.

But Justice Clarence Thomas cast doubt on Mr. Garland’s thinking just two weeks ago, in his concurring opinion in the Trump immunity case that the Supreme Court decided July 1.

Justice Thomas said Congress must create an office for a president to fill, and Congress has not specifically created the special counsel. He said the laws Mr. Garland cited in appointing Mr. Smith were general in nature and didn’t conclusively justify a special counsel.

“If there is no law establishing the office that the Special Counsel occupies, then he cannot proceed with this prosecution. A private citizen cannot criminally prosecute anyone, let alone a former President,” Justice Thomas wrote.

Judge Cannon on Monday agreed, saying Mr. Garland did an end-run around the Appointments Clause.

“The bottom line is this: The Appointments Clause is a critical constitutional restriction stemming from the separation of powers, and it gives to Congress a considered role in determining the propriety of vesting appointment power for inferior officers,” the judge wrote. “The Special Counsel’s position effectively usurps that important legislative authority, transferring it to a Head of Department, and in the process threatening the structural liberty inherent in the separation of powers.”

Mr. Trump faced 40 felony counts in the indictment, which accused him of unlawfully taking classified government records to his Florida home and then obstructing national archivists’ attempts to retrieve them.

Walt Nauta, a valet for Mr. Trump, and Carlos De Oliveira, a property manager at Mar-a-Lago, were also charged.

Prosecutors said the removal of sensitive documents was a grave threat to national security, and the indictment was seen as one of the more straightforward cases against Mr. Trump until Judge Cannon’s ruling.

Mr. Trump insisted he had de facto power to take the records because he’d once been president and said they were mixed in with other keepsakes from the White House in an array of boxes at his estate. He also complained about the 2022 FBI raid on his estate.

Judge Cannon is overseeing Mr. Smith’s classified documents prosecution.

Mr. Smith is also handling another criminal prosecution in Washington, overseen by Judge Tanya Chutkan, accusing Mr. Trump of trying to upend the results of the 2020 election.

That case is on hold as all sides try to grapple with the Supreme Court’s immunity ruling, which found at least some of Mr. Trump’s actions related to the election are protected by presidential immunity.

Mr. Trump also faces state racketeering charges in Georgia stemming from his 2020 election actions.

And he has been convicted in a court in New York of falsifying business records. Mr. Trump is awaiting sentencing but has challenged the guilty verdict in that case in light of the Supreme Court’s immunity ruling.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.

• Tom Howell Jr. can be reached at thowell@washingtontimes.com.