Trump's theory of absolute criminal immunity means this:
If Trump, on his last day in office, shot someone on 5th Avenue in front of thousands of witnesses, there could be no criminal investigation until (1) The House impeached him and (2) The Senate convicted him.
If 2/3 of the Senate refused to convict him, he would walk free.
It's possible he couldn't even be impeached because impeachment, under some theories, addresses only crimes of office, and abuse of power.
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