I did watch it. I don't have time to research the case law in that particular jurisdiction today. Too busy doing my own work. That said, I think it's enough to get a prosecutor to sign the probable cause affidavit and say 'let a jury sort it out.'
With all due respect, if yours had been a very good way to explain the legal standard in layman terms, we wouldn't be having this discussion. I noted above that your description might pass in casual conversation, but this is the Legal forum. We have to keep a much tighter rein on our words and postings in here.
As for the shortcomings in your description, I'll point them out in the hopes that it will be helpful.
"Something specific" -- I'll give you that one. In order to be an actionable threat, a certain degree of specificity is required.
"To someone" -- It doesn't have to be 'to someone.' A threat to damage property may be actionable. This one's good enough for casual conversation, but not for a discussion of legal issues.
"Then only if people believe them" -- Which people? The target of the threat? Prosecutors? Police? General witnesses who may have heard the threat (or seen it if written)? So if I post threats to the President of the United States, does he have to believe I would carry those threats out for it to be a crime? No. The word "people" is horribly vague in this context, and the "only if people believe them" is flat not true. I'm at my desk today, so I'll pull the Arkansas Statute on Terroristic Threatening:
There is zero language in the AR statute about the target having to believe that the threat will be carried out.
"Running their mouth" -- That's a phrase that's fine for casual conversation, but it hasn't appeared in any statute or case that I've ever read in my career.
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