In a 1985 memo to the White House’s top lawyer, now chief justice John Roberts wrote that a president may not block congressionally required spending — a declaration on a major legal question that now seems destined to move from the Trump White House to Roberts’s Supreme Court.

On Tuesday, President Donald Trump’s administration issued an order declaring that “all agencies must temporarily pause all activities related to obligation or disbursement of all federal financial assistance.” The directive — which sowed chaos throughout the country’s Medicaid and Head Start programs — was temporarily stayed by a federal judge. But the dispute over spending authority has created a constitutional crisis that is likely to be appealed up to the high court.

Roberts already outlined his views on such powers during his tenure in President Ronald Reagan’s White House Counsel’s Office.

In a 1985 communiqué unearthed by us, Roberts weighed in on a question from Reagan’s staff secretary, David Chew, about a president’s alleged power to block — or, in budget terms, impound — spending legislated by Congress.

In that memo, Roberts declared that “the question of whether the president has such authority (to block congressionally mandated spending) is not free from doubt, but I think it clear that he has none in normal situations.”

Roberts added:

We should discourage Chew and others from considering impoundment as a viable budget planning option. Our institutional vigilance with respect to the constitutional prerogatives of the presidency requires appropriate deference to the constitutional prerogatives of the other branches, and no area seems more clearly the province of Congress than the power of the purse.

According to Daniel Schuman, an attorney and executive director of the American Governance Institute, which advocates for government transparency, Roberts’s writing on the matter is clear.

“John Roberts’ August 1985 memorandum clearly articulates his legal opinion that the president cannot exceed the Impoundment Control Act to impound funds in ‘normal’ situations, perhaps not in any circumstances,” said Schuman:

Roberts declares the power of the purse is the ultimate congressional prerogative. Impoundment, he warns, cannot be used to achieve “budget goals,” yet the stated goal of Trump’s OMB Memorandum 25-13 is for “advancing presidential priorities” on a wide array of issues. There is no reconciling Roberts’ views with Trump’s facially unlawful impoundment directive.”

Roberts’s 1985 memo was directly referencing — and reinforcing — his office’s more detailed memo on the subject, which declared that “the president has no independent constitutional authority to impound funds.”

That memo quoted another future Supreme Court chief justice — William Rehnquist — making much the same point in 1969 during his tenure in President Richard Nixon’s Justice Department. Nixon’s attempts to impound spending prompted Congress to pass landmark legislation aiming to outlaw the practice.

“With respect to the suggestion that the President has a constitutional power to decline to spend appropriated funds, we must conclude that existence of such a broad power is supported by neither reason nor precedent,” Rehnquist wrote in 1969 while serving as assistant attorney general. “It is in our view extremely difficult to formulate a constitutional theory to justify a refusal by the president to comply with a congressional directive to spend.”

Rehnquist went on to note:

It may be argued that the spending of money is inherently an executive function, but the execution of any law is, by definition, an executive function, and it seems an anomalous proposition that because the executive branch is bound to execute the laws, it is free to decline to execute them.

Georgetown Law professor Steve Vladeck noted that in 1988, the Reagan Justice Department concluded that when it comes to impoundment, the law “is against such a broad power in the face of an express congressional directive to spend.”

“There is no textual source in the Constitution for any inherent authority to impound,” Reagan’s assistant attorney general, Charles J. Cooper, wrote at the time. “Arguments in favor of an inherent impoundment power, carried to their logical conclusion, would render congressional directions to spend merely advisory.”