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No president has ever been forced out via impeachment. And the Supreme Court has never been called to review and/or undo an impeachment or to negate the reasons for any particular impeachment.

However, the role of the Supreme Court has never been clear:

The Role of the U.S. Supreme Court

The Supreme Court of the United States has decided that it should not review judicial impeachments, using the "political question" doctrine to sidestep the issue. Walter Nixon v. United States, 506 U.S. 224 (1993). In the Walter Nixon case, Judge Nixon attacked the rule of the Senate allowing a subcommittee to hear evidence, rather than the Senate as a whole, in his judicial impeachment. The opinion of the Supreme Court declined to review Judge Nixon's case, and in dicta is not binding on future Courts.

Even though the Court was unanimous in concluding not to review Judge Nixon's removal from office, there were multiple concurring opinions. The concurring opinion of Justice White indicates an unwillingness, on his part at least, to conclude in advance that a Presidential impeachment would be unreviewable. See Walter Nixon v. United States, 506 U.S. at 244. As stated by Justice White at footnote 3, page 247 of the Walter Nixon case:

"Finally, as applied to the special case of the President, the majority's argument merely points out that, were the Senate to convict the President without any kind of trial, a Constitutional crisis might well result. It hardly follows that the Court ought to refrain from upholding the Constitution in all impeachment cases. Nor does it follow that, in cases of Presidential impeachment, the Justices ought to abandon their constitutional responsibilities because the Senate has precipitated a crisis."

This view is echoed by Justice Souter in his concurring opinion in the same case:

"If the Senate were to act in a manner seriously threatening the integrity of its results...judicial interference might well be appropriate." Walter Nixon v. United States, 506 U.S. at 253.