‘The states have no power, by taxation or otherwise, to retard, impede, burden, or in any manner control, the operations of the constitutional laws enacted by congress to carry into execution the powers vested in the general government. This is, we think, the unavoidable consequence of that supremacy which the constitution has declared.’

We hope that at some point the lawyers going after President Trump in New York and Georgia will study those words. They were penned in 1819 by the chief justice of the United States, John Marshall, in one of the most important cases in American history — McCulloch v. Maryland. The court unanimously blocked Maryland from taxing the Second Bank of the United States. “The power to tax involves the power to destroy,” the court growled.

What then, of the power to prosecute? That is the question that surfaces as Trump prepares to take the oath of office and two state prosecutors  — District Attorneys Alvin Bragg and Fani Willis — make the case that their prosecutions of Trump can survive the four years of his second term. That is an untested proposition because a sitting president has never faced criminal charges. Mr. Bragg wants his case delayed. Ms. Willis appears intent on charging ahead. 

Trump’s motion to dismiss Ms. Willis’s racketeering charges cites McCulloch as a case from “the dawn of the Republic.” The President-elect’s brief cites McCulloch’s holding that states “have no power … to retard, impede, burden, or in any manner control, the operations” of the federal government. The states do retain the police power, unless it conflicts with the Supremacy Clause, which declares federal law part of the “supreme law of the land.”

Welcome to the unfolding of the law of presidential immunity in real time. The Supreme Court in Trump v. United States ruled that official presidential acts are presumptively immune, while unofficial or private ones enjoy no such protection. In the New York case, Judge Juan Merchan has ruled that Mr. Bragg’s 34 convictions survive that standard. Mr. Smith thought the same of his case, but the Office of Legal Counsel ordered him to desist. 

The OLC, whose rulings bind the Department of Justice, has now thrice held that there is a “categorical” prohibition on prosecuting a sitting president. In 2000, the office wrote that “the indictment or criminal prosecution of a sitting President would unconstitutionally undermine the capacity of the executive branch to perform its constitutionally assigned functions.” Mr. Smith bowed to that guidance in requesting dismissal. 

What about Clinton v. Paula Corbin Jones? That was a civil dispute. The Supreme Court has held that civil suits do not pose the same threat to presidential prerogative. In Clinton, the Nine held that the 42nd president — and all subsequent ones — possessed no immunity while in office for acts done before taking office and unrelated to the office of the presidency. That decision was unanimous. Trump also faces civil suits stemming from January 6.

In respect of McCulloch, a state prosecution of a sitting president appears to present a prima facie injury to federal sovereignty. In a 1807 letter to George Hay from Thomas Jefferson at Monticello, the Pen of the Revolution worried what would be if “the several courts could bandy” the president “from pillar to post, keep him constantly trudging from north to south & east to west, and withdraw him entirely from his constitutional duties.”

Jefferson was contemplating the federal judiciary. How much more so is the threat to a sitting president posed by elected local prosecutors and judges? To insist that a president enjoy four years of protection to do his job is not to make him a king. Marshall wrote in McCulloch that “the government of the Union, though limited in its powers, is supreme within its sphere of action.” Is the prosecutor’s power to destroy any less than the taxman’s?