President Trump’s press secretary, Karoline Leavitt, is offering a stalwart defense of the commander in chief’s power to fire federal employees. “He is the executive of the executive branch, and therefore he has the power to fire anyone within the executive branch that he wishes to,” she tells CNN’s Kaitlan Collins. It could be an uphill climb, though the administration is, by our lights, planting its flag on constitutional bedrock. 

Ms. Leavitt’s remarks today came amid questions about Mr. Trump cashiering several Justice Department prosecutors who worked on Jack Smith’s lawfare campaign, along with some 18 inspectors general imposed on the executive branch by Congress. “The legality of the ousters last week has been questioned by Democrats and even by some Republicans,” Axios reports, due to civil service protections and requirements set by Congress.

The president’s defiance of these laws, and Ms. Leavitt’s clear-cut appraisal of the matter, tees up a dispute that could have to be settled by the Supreme Court. This would be long overdue, as these columns noted when Mr. Trump previewed his plans to fire the DOJ lawyers, “over the thicket of laws that shield federal civil servants from being fired.” The conflict could prove decisive to the success of Mr. Trump’s and other presidencies.

In a possible preview of the president’s legal strategy, Ms. Leavitt pointed to a 2020 Supreme Court precedent, Seila Law v. Consumer Financial Protection Bureau, where the Nine found that the head of that federal agency “must be removable by the President at will.” Seila Law, though, features caveats that could impinge on Mr. Trump’s freedom of action. The Nine marked a president’s power to fire a policymaker but conceded Congress can shield an “inferior officer” from termination. 

Yet Seila Law was decided by a narrow majority, five to four, and its precedent could find itself reevaluated by a more conservative high court. To be sure, the question of whether the president can be constrained in executive branch personnel matters has been hotly debated — and largely settled in favor of the chief executive — since the earliest days of the republic. It even prompted the first attempt to impeach a president — Andrew Johnson — in 1868.

Johnson ran afoul of Congress by firing his Secretary of War, infuriating his opponents on Capitol Hill. Johnson’s acquittal was, in a sense, a vindication of a president’s right to choose his own personnel, which is critical to his or her ability to take care that our laws are faithfully executed. That was in keeping with the spirit of the early days of the Republic, when presidents were unfettered in hiring and firing executive branch employees. 

The so-called “Spoils System,” though, offended critics who wanted “merit” to be the basis for hiring federal staffers. That was the pretext, in 1883, for the Pendleton Act, a cloak for partisanship as the GOP, which had lost control of the House, sought to protect its own party employees in the executive branch. At the time, a Sun editorial suggested that the new Civil Service Commission infringed on the president’s appointment powers.

That was an early warning of how “Civil Service Reform” amounted to a bolstering of the federal bureaucracy at the expense of presidential prerogatives. It helped to lay the foundations for what historian Williamjames Hoffer would go on to call a “fully developed regulatory state.” Legal protections for federal employees would grow until, under President Carter, it became virtually impossible to fire any of them.

Grasping the extent of this problem, President Trump in his first term sought to reform the civil service by executive order. The clock ran out before his changes could go into effect. It’s no wonder, then, that he is tackling this issue out of the gate in his second term. It is worth every bit of a long and determined constitutional battle all the way to the Supreme Court. Ms. Leavitt was smart as a whip to mark the point as emphatically as she did.