“This great nation can tolerate a president who makes mistakes,” declared Senator Orrin Hatch, the Utah Republican. “But it cannot tolerate one who makes a mistake and then breaks the law to cover it up.”

No, Mr. Hatch wasn’t talking about Donald Trump. It was 1999, and he was talking about Bill Clinton.

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Now Mr. Hatch and his fellow lawmakers may be approaching a harsher and more consequential test. We quote his words not to level some sort of accusation of hypocrisy, but to remind us all of what is at stake.

News reports point to a growing possibility that President Trump may act to cripple or shut down an investigation by the nation’s top law-enforcement agencies into his campaign and administration. Lawmakers need to be preparing now for that possibility because if and when it comes to pass, they will suddenly find themselves on the edge of an abyss, with the Constitution in their hands.

https://www.nytimes.com/interactive/2018/04/15/opinion/editorials/president-above-rule-law.html