Plus there's this little thing called double jeopardy -which means you can't indict/prosecute the person on the same charges later if more evidence of their guilt comes up. So, prosecutors generally don't go forward with an indictment unless they think they have a good chance of winning. Anyone who has watched Law & Order knows that - never mind someone with even a passing knowledge of the criminal justice system.
You can't prosecute someone for the same crime twice once they have been tried. If there has been no trial, or charges dropped (prejudice matters), they can be indicted again.
Television shows have never given an accurate schooling on the law. This includes Law & Order.
Prosecutor decisions are only generally predictable. They have legal discretion nonetheless.
I don't ike it but this is not going to get past the Senate - they won't be able to impeach him again for these offences - and he will have an even greater sense that he is beyond the reach of law than he already does.
Case in point for your Law & Order course selection:
Impeachment in the Constitution is irrespective of criminal law.
There is no double jeopardy limitation.
Repeated impeachment for the same crimes *is* possible.