In the Supreme Court's monumental decision in former President Trump's immunity case, one justice questioned whether Special Counsel Jack Smith – at the helm of Trump's unprecedented prosecution – was constitutionally appointed. 

On Monday, a 6-3 majority ruled that a president has substantial immunity for official acts in office, and sent the case back down to lower courts to determine which acts at the center of Trump's case were official. 

"The President is not above the law. But Congress may not criminalize the President’s conduct in carrying out the responsibilities of the Executive Branch under the Constitution. And the system of separated powers designed by the Framers has always demanded an energetic, independent Executive," the opinion said. 

In a separate concurring opinion, Justice Clarence Thomas looked to "highlight another way in which this prosecution may violate our constitutional structure" – the appointment of Jack Smith as special counsel. 

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"In this case, there has been much discussion about ensuring that a President ‘is not above the law.’ But, as the Court explains, the President’s immunity from prosecution for his official acts is the law. The Constitution provides for ‘an energetic executive,’ because such an Executive is ‘essential to… the security of liberty,'" Thomas wrote. 

"Respecting the protections that the Constitution provides for the Office of the Presidency secures liberty. In that same vein, the Constitution also secures liberty by separating the powers to create and fill offices. And, there are serious questions whether the Attorney General has violated that structure by creating an office of the Special Counsel that has not been established by law," Thomas said, adding that "[t]hose questions must be answered before this prosecution can proceed."

Thomas explained that in this case, the attorney general "purported to appoint a private citizen as Special Counsel to prosecute a former President on behalf of the United States." 

"But, I am not sure that any office for the Special Counsel has been ‘established by Law,’ as the Constitution requires. By requiring that Congress create federal offices ‘by Law,’ the Constitution imposes an important check against the President – he cannot create offices at his pleasure," he said. 

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"If there is no law establishing the office that the Special Counsel occupies, then he cannot proceed with this prosecution." he said. 

Thomas added that "a private citizen cannot criminally prosecute anyone, let alone a former President."

Thomas noted that "[n]o former President has faced criminal prosecution for his acts while in office in the more than 200 years since the founding of our country. And, that is so despite numerous past Presidents taking actions that many would argue constitute crimes. If this unprecedented prosecution is to proceed, it must be conducted by someone duly authorized to do so by the American people." 

The question of what immunity should be granted to Trump and future presidents stemmed from Smith’s federal election interference case in which he charged Trump with conspiracy to defraud the United States; conspiracy to obstruct an official proceeding; obstruction of and attempt to obstruct an official proceeding; and conspiracy against rights. 

Those charges were the result of Smith’s months-long investigation into whether Trump was involved in the Jan. 6, 2021, Capitol riot and any alleged interference in the 2020 election results. Trump pleaded not guilty to all charges and argued he should be immune from prosecution from official acts done as president.

In an amicus brief filed in the case before the high court, Ed Meese, attorney general under President Ronald Reagan, argued that the court should reject Special Counsel Jack Smith’s request because he was unconstitutionally appointed in the first place. 

"Not clothed in the authority of the federal government, Smith is a modern example of the naked emperor," the brief stated. 

"Improperly appointed, he has no more authority to represent the United States in this Court than Bryce Harper, Taylor Swift, or Jeff Bezos," he argued. 

Merrick Garland cited statutory authority for Smith's appointment, none of which Meese argued "remotely authorized the appointment by the Attorney General of a private citizen to receive extraordinary criminal law enforcement power under the title of Special Counsel."

Thomas acknowledged that argument in his concurrence, saying, "It is difficult to see how the Special Counsel has an office ‘established by Law,’ as required by the Constitution. When the Attorney General appointed the Special Counsel, he did not identify any statute that clearly creates such an office."

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Meese also argued that "even if one overlooks the absence of statutory authority for the position, there is no statute specifically authorizing the Attorney General, rather than the President by and with the advice and consent of the Senate, to appoint such a Special Counsel."

"Under the Appointments Clause, inferior officers can be appointed by department heads only if Congress so directs by statute… and so directs specifically enough to overcome a clear-statement presumption in favor of presidential appointment and senatorial confirmation. No such statute exists for the Special Counsel," he added.

Thomas on Friday argued similarly. 

"Even if the Special Counsel has a valid office, questions remain as to whether the Attorney General filled that office in compliance with the Appointments Clause," he said. 

"For example, it must be determined whether the Special Counsel is a principal or inferior officer. If the former, his appointment is invalid because the Special Counsel was not nominated by the President and confirmed by the Senate, as principal officers must be," he said.

"Those questions must be answered before this prosecution can proceed," he added.

"We must respect the Constitution’s separation of powers in all its forms, else we risk rendering its protection of liberty a parchment guarantee," he concluded.