The New York Times Editorial Board, in a piece entitled "The President is Not Above the Law," writes the following:
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.
Make no mistake: If Mr. Trump takes such drastic action, he will be striking at the foundation of the American government, attempting to set a precedent that a president, alone among American citizens, is above the law. What can seem now like a political sideshow will instantly become a constitutional crisis, and history will come calling for Mr. Hatch and his colleagues.
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A few senior Republicans have been saying the right things — including Mr. Hatch. He tweeted that anyone telling the president to fire Mr. Mueller “does not have the President or the nation’s best interest at heart.” Senator Lindsey Graham, of South Carolina, warned Mr. Trump that firing Mr. Mueller would be “the beginning of the end of his presidency.”
That’s all necessary and good. But it’s not enough. More Republicans need to make it clear that they won’t tolerate any action against either man, and that firing Mr. Mueller would be, as Senator Charles Grassley said, “suicide.”
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The president is not a king but a citizen, deserving of the presumption of innocence and other protections, yet also vulnerable to lawful scrutiny. We hope Mr. Trump recognizes this. If he doesn’t, how Republican lawmakers respond will shape the future not only of this presidency and of one of the country’s great political parties, but of the American experiment itself.
Read the full editorial: THE PRESIDENT IS NOT ABOVE THE LAW (NYT)