A new Supreme Court ruling has sharply narrowed Donald J. Trump’s legal options, escalating a long-running dispute over withheld materials and underscoring a growing institutional willingness to enforce compliance—even against a former president.

WASHINGTON — The Supreme Court on Monday issued a forceful order directing former President Donald J. Trump to comply immediately with a federal directive to turn over disputed materials, a ruling that legal experts say significantly heightens the risk of contempt proceedings if he fails to do so.

While the court’s decision stopped short of explicitly threatening incarceration, its language left little ambiguity about the consequences of defiance. Lower courts were authorized to enforce compliance without delay, a step that places Mr. Trump in an increasingly precarious legal position and signals the judiciary’s impatience with prolonged resistance.

For months, Mr. Trump’s legal team has relied on a familiar strategy: delay, appeal, and broad assertions of executive privilege and presidential immunity. The Supreme Court’s ruling sharply constrains those arguments, closing off procedural avenues that had previously slowed enforcement.

“This is the end of the road for stalling tactics,” said one former federal judge, speaking on condition of anonymity to discuss internal court dynamics. “The court is saying, in unmistakable terms, that compliance is not optional.”

A Court Asserting Its Authority

The ruling carries particular weight because it comes from a Supreme Court reshaped by Mr. Trump himself. During his presidency, he appointed three justices, helping to solidify a conservative majority that many of his allies believed would remain sympathetic to his legal arguments.

Instead, the court’s action reflects a different calculus. Legal scholars note that institutional legitimacy, not personal loyalty, appears to be driving the justices’ approach.

“The Supreme Court is acutely aware that its authority depends on the perception that no individual is above the law,” said Linda Greenfeld, a constitutional law professor at Georgetown University. “Allowing a former president to openly defy a binding order would undermine that authority.”

Chief Justice John G. Roberts Jr., in particular, has repeatedly emphasized the court’s role as an independent arbiter rather than a political actor. Analysts say the ruling fits a broader pattern of the court distancing itself from partisan narratives, especially in cases that test the limits of executive power.

What Is at Stake

At the center of the dispute are materials that federal authorities say Mr. Trump has improperly withheld despite prior court orders. While details remain sealed, the documents are believed to include sensitive records that investigators argue are essential to ongoing inquiries.

Mr. Trump has claimed that the materials are protected by executive privilege and that their release would be unlawful. Courts at multiple levels have rejected those arguments, ruling that the privilege does not apply in the manner Mr. Trump asserts, particularly after leaving office.

If Mr. Trump refuses to comply, the most immediate risk is a finding of civil contempt. Under longstanding legal doctrine, judges may impose escalating penalties — including fines or confinement — designed to compel compliance rather than punish past behavior.

“It’s sometimes described as ‘holding the keys to your own cell,’” said Andrew Weissman, a former federal prosecutor. “The moment you comply, the sanction ends.”

Political Repercussions

The ruling lands at a volatile political moment, with Mr. Trump again seeking the presidency and framing his legal troubles as evidence of political persecution. In public statements, he has accused the judiciary of being “weaponized” against him, a claim his supporters have echoed.

But the fact that the order comes from a conservative-dominated Supreme Court complicates that narrative.

“This isn’t coming from ideological opponents,” said a Republican strategist who has advised multiple presidential campaigns. “That makes it harder to dismiss as partisan.”

Inside Trump-aligned circles, the decision has triggered concern about donor confidence and campaign viability. Major contributors, wary of legal uncertainty, have increasingly signaled hesitation, according to people familiar with fundraising discussions.

“A candidate facing potential contempt sanctions from the Supreme Court is a risk many donors won’t take,” the strategist said.

The Administration’s Calculated Silence

Notably absent from the immediate reaction was commentary from the Biden-Harris administration. White House officials declined to address the ruling directly, citing respect for judicial independence.

That restraint appears deliberate. By allowing the courts to act without executive commentary, the administration avoids reinforcing claims of political interference while allowing legal institutions to assert their authority independently.

Vice President Kamala Harris, a former prosecutor, has previously emphasized that accountability is a matter for the justice system, not electoral politics. Allies say that philosophy remains unchanged.

A Test of Compliance

The most consequential question now is whether Mr. Trump will comply.

History offers mixed signals. In past disputes, he has oscillated between defiance and reluctant adherence when faced with unavoidable enforcement. Legal analysts say the compressed timeline implied by the court’s ruling leaves little room for maneuver.

“Once a compliance deadline passes, the process moves very quickly,” said Greenfeld. “At that point, the issue isn’t politics. It’s enforcement.”

Federal authorities, including the Department of Justice and U.S. Marshals Service, routinely prepare contingency plans for high-profile compliance actions. Officials declined to comment on operational details, but experts say such preparations are standard when court orders carry the possibility of contempt.

Broader Implications

Beyond Mr. Trump’s personal legal exposure, the ruling carries broader significance for the American legal system. It underscores the judiciary’s willingness to enforce its orders against even the most powerful figures and reinforces a core constitutional principle: that the rule of law applies universally.

“This is a stress test for the system,” Weissman said. “If the courts cannot enforce compliance here, their authority is diminished everywhere.”

For Mr. Trump, the decision represents a narrowing funnel of options. Compliance could expose him to further legal risk, while defiance risks immediate sanctions. Either path carries political and personal consequences.

As deadlines approach, attention will focus on court filings, official statements from his legal team, and any indication of movement by enforcement authorities. The outcome will not only shape Mr. Trump’s legal future but may also mark a defining moment in the ongoing effort to clarify the limits of presidential power in the post-presidency era.

For now, the Supreme Court has spoken clearly. What remains is whether a former president will heed that command — or test the consequences of refusing to do so.