A judge on Tuesday restored Cathy Harris to her job as chairwoman of the federal Merit Systems Protection Board, ruling that President Trump’s attempt to fire her was illegal.

Judge Rudolph Contreras said Ms. Harris was in the middle of her term and under the law she can be fired only for good reasons, adding that since Mr. Trump gave no such reason, the ouster can’t stand.

“Cathy A. Harris shall continue to serve as a member of the Merit Systems Protection Board until her term expires pursuant to 5 U.S.C. § 1202, unless she is earlier removed for inefficiency, neglect of duty, or malfeasance in office under that statute,” the judge ordered.

The MSPB hands down rules on federal personnel matters and is considering cases involving other Trump firings. Ms. Harris’ membership could impede the president’s plans.

Trump’s lawyers argued the president needs unfettered powers to put his people in key positions and that blocking that power undermines his ability to run his administration.

But Judge Contreras said a 90-year-old Supreme Court precedent has established that “independent agencies” are different, with their leaders often insulated from the usual politics of regular executive branch offices.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.