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In the years after Watergate, Justice Department officials — from both parties — worked hard to banish partisan cronyism from the department. Their goal was to make it the least political, most independent part of the executive branch.

“Our law is not an instrument of partisan purpose,” Edward Levi, Gerald Ford’s attorney general, said at the time. Griffin Bell, later appointed to the same job by Jimmy Carter, described the department as “a neutral zone in the government, because the law has to be neutral.”

Attorney General William Barr clearly rejects this principle. He’s repeatedly put a higher priority on protecting his boss, President Trump, than on upholding the law in a neutral way. He did so in his letter last month summarizing Robert Mueller’s investigation and then again in a bizarre prebuttal news conference yesterday. As The Times editorial board wrote, Barr yesterday “behaved more like the president’s defense attorney than the nation’s top law-enforcement officer.”