The Supreme Court for the first time put limits on congressional power to subpoena a sitting president’s personal and business information, in a ruling Thursday that will frustrate the House’s effort to get President Donald Trump’s before the November election.

The 7-2 opinion, in one of the most closely watched cases of the term that ended Thursday, did not resolve the legal battle between Trump and the House over committee subpoenas for records from auditing firm Mazars USA and two banks, Capital One and Deutsche Bank.

Instead, Chief Justice John G. Roberts Jr., writing for the court, laid out what Congress and the courts must do before subpoenas for a president’s records can be enforced. And then the Supreme Court sent the case back to lower courts to look at the case again.

The decision diffuses any political bomb before the November election had there been more information on a number of ongoing congressional probes, such as the House Intelligence Committee look into efforts by Russia and other foreign entities to influence the U.S. political process during and since the 2016 presidential election.

The opinion reflects a discomfort among the justices with the House claim to almost limitless power to subpoena documents related to a legislative purpose — and a fear of what kind of political weapon that could become.

The Trump-House conflict is the first to get to the Supreme Court, and historically the two political branches have grappled with each other over such congressional requests for a president’s papers, Roberts wrote.

But a limitless subpoena power would “transform” that, Roberts wrote, and “Congress could ‘exert an imperious control’ over the Executive Branch and aggrandize itself at the President’s expense, just as the Framers feared.”

“Instead of negotiating over information requests, Congress could simply walk away from the bargaining table and compel compliance in court,” Roberts wrote.

Any personal paper a president had could potentially “relate to” a conceivable subject of legislation, Roberts wrote. Financial records could relate to economic reform, medical records to health reform, and more.

And it doesn’t matter if those records are with a third party like Mazars, Roberts wrote, because Congress could then sidestep any separation-of-powers concerns for information like cell phone location data that a company retains.

“Indeed, Congress could declare open season on the President’s information held by schools, archives, internet service providers, e-mail clients, and financial institutions,” Roberts wrote.

Instead, the majority opinion lays out a new test of sorts for congressional subpoenas for a president’s records.

Congress must show whether it can go to “other sources” for the information it needs, and it is not enough to say that they are looking at a president as a “case study” for general legislation, the opinion states.

The subpoena should be as specific as reasonably necessary to support lawmakers’ legislative intent. It should not be a burden on the president. And Congress should identify its reasons, and the “more detailed and substantial the evidence” the better, the court wrote.

The Supreme Court also left open the door to more limits in the future. “Other considerations may be pertinent as well; one case every two centuries does not afford enough experience for an exhaustive list,” Roberts wrote.

Roberts and the majority also rejected the arguments from Trump’s personal lawyers, as well as the Justice Department, for more sweeping legal protection for a president’s papers even when they do not deal with executive branch deliberations.

That “would risk seriously impeding Congress in carrying out its responsibilities, and give “short shrift to Congress’s important interests in conducting inquiries to obtain the information it needs to legislate effectively.”

Speaker Nancy Pelosi said that with that holding, the Supreme Court backed congressional oversight power, preserved the checks and balances between the legislative and executive branches, and kept the idea that a president is not above the law.

“The process will take longer, but that’s not what is important, what was truly important, here,” the California Democrat told reporters.

Trump has not prevailed in any of the lower court rulings that led to this Supreme Court challenge, but had stymied the House efforts for the documents for more than a year.

In April 2019, the House Oversight Committee issued a subpoena to Mazars USA, the accounting firm for Trump and several of his business entities, for eight years of accounting and other financial information from both before and after he took office.

The House says the probe relates to three areas: Concerns about Trump’s business interests in the federal Old Post Office Building for the Trump International Hotel in Washington; the adequacy of Trump’s financial disclosures because of the omission of $130,000 paid by the president’s former personal attorney, Michael Cohen, to adult film star Stormy Daniels; and testimony from Cohen that Trump inflated and deflated real estate values to reduce his tax burden.

Also in April 2019, the House Financial Services and Intelligence committees issued three subpoenas to Capital One and Deutsche Bank for records related to Trump and his family members, part of an industry-wide investigation into financial institutions’ compliance with banking laws, the House told the Supreme Court.

The committee pointed to reports of links between the banks, money laundering enforcement, loans to Trump and Trump businesses, and “questions regarding Deutsche Bank’s suspicious or high-risk transactions involving Russia, President Trump, or both.”

Two of the subpoenas are identical and ask for information about seven business entities and the personal accounts of Trump and three of his children, Donald Trump Jr., Eric Trump and Ivanka Trump.

The Intelligence Committee says it is part of an investigation into efforts by Russia and other foreign entities to influence the U.S. political process during and since the 2016 presidential election.

Lindsey McPherson contributed to this report.