Nixon should have never been brought down over a third rate burglary anyhow.
Nixon never should have covered up a third rate burglary (that he probably didn't authorize).
If that's all it was, I don't think he would have bothered covering it up.
The first article of impeachment was the obstruction of justice, which was pretty massive.
http://www.historyplace.com/unitedstates/impeachments/nixon.htmThe second article, abuse of power, was weaker, because you could make an argument that this is just the nature of the incumbency.
The third article, contept of Congress, is hard to justify, as Nixon surrendered the documents Congress wanted, after court action. He basically claimed that he had a right, in the Constitution, to Executive Privilege. So far as I can remember, it was never tested in a criminal action before.
Now, while the second one was weak, and the third one, exceptionally bad, constitutionally, the first one was probably the strongest and I would have voted impeachment/conviction on that one.
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