As I have posted before, it is looking more and more likely that President Trump will be indicted shortly after the inauguration. As of right now, he is a very popular man, and the most serious threat that the Democrats face in terms of opposition.
There has been talk of President Trump pardoning himself, but that opens him up to all sorts of legal challenges. As the article says:
An attempt at a self-pardon would be an unprecedented move and could very well face legal challenges.
There is a way that the President can beat this. The 25th Amendment. Let me explain:
At 10:00 am on the 20th of January, the President transmits a written statement to Mitch McConnel and Nancy Pelosi that he is unable to fulfill the duties of his office. The Vice President immediately becomes the President of the United States, and as his first official act, he pardons the now former President.
If this is timed correctly, there would be nothing that the Democrats could do about it.