Trump made a creative, non-frivolous argument that he has absolute immunity from criminal prosecution.
It's also clear that he will lose in the courts. The courts (including SCOTUS) shot down his executive privilege claims, and that was a closer question and less ridiculous than his absolute criminal immunity claim.
It was obvious he was going to lose. The question was: How long would it take?
Smith is short-circuiting the process and going straight to SCOTUS.
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