Many made this claim, as did some in this @vox round-up.
In my contribution, I say this is a legal & political mistake.
Today's tweets are part of an impeachable pattern of abuse, but not criminal. 1/
vox.com/2019/11/15/209…
"There is another valid concern that a president's harsh speech is far more dangerous than anyone else's in putting a target on the back of witness...
Mueller explained that he avoided any clear conclusions about Trump's crimes because of (an overwrought) concern about fairness if a president couldn't be indicted & get his day in court to defend himself...
Presidents have plenty of ways to defend themselves without needing a day in court. They have a bully pulpit and twitter, etc...
Either way, prosecutors should be able to accuse a president clearly.
But that argument also depends on giving presidents their free speech to defend themselves, including criticizing witnesses (as long as there is no threat).