A long-simmering showdown over whether President Donald Trump may seize control over the Federal Reserve appears to be entering its endgame. It is highly likely that the Supreme Court will weigh in on this dispute either Monday evening or Tuesday.

If the Court does side with Trump, that would be one of the most consequential economic policy decisions in the federal judiciary’s history. And it could potentially have disastrous consequences both for investors and for the US economy broadly.

The Fed is one of several federal agencies that are labeled as “independent” from the president. Though the president chooses who will serve on the Fed’s Board of Governors, these governors must be confirmed by the Senate, and they serve 14-year terms. By law, the president may only remove a member of the Fed’s board “for cause,” unlike most agency leaders who serve at the pleasure of the president.

The Supreme Court’s Republican majority, however, subscribes to a theory known as the “unitary executive,” which claims that it is unconstitutional for Congress to shield agency leaders from presidential control. If you care about the details of this theory, I’ve written more explainers on it than I can count, but the gist of it is that the Constitution places all “executive” power in the hands of the president. So any agency leader who wields authority that the Court deems to be “executive” in nature must be fireable at will by the president.

For most of the past two decades, the Republican justices have

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