Suppose I know a person (Mr. Bloggins) is about to testify before a grand jury about my many, many, crimes. I posts on social media “Mr. Bloggins is about to testify before the grand jury. He shouldn’t. I barely know Mr. Bloggins. He has always been part of the witch hunt to get me.”
Is this witness tampering?
Yes it is, it has an implied threat when they say he shouldn’t. It could also be called an attempt to discredit the witness with the jury.
Thanks!
You are correct sir.
Thanks! Additional confirmation is appreciated. 
I think it is obvious who this is about, and I’ve seen a lot of redditors say this is a clear case of witness tampering but, I hate it when my source of knowledge is “reddit”. I have a lot more trust in the people here to be accurate, especially in FQ.
It seems to me if a witness is sworn to tell “the truth, the whole truth, and nothing but the truth” then advising them to not tell any of the truth is tampering, no different than telling them not to tell the whole truth. Plus, if a person receives a subpoena, they are essentially obliged to attend and testify. Telling them not to would be counselling them to commit contempt of court, would it not?
You have presented a hypothetical case. It’s not witness tampering based on what you have presented. If you’re some 2 bit criminal with no influence on others then you haven’t stated anything like a threat or any reason that Bloggins would be dissuaded from testifying. Your statement on it’s face is not witness tampering.
It looks like he’s also attempting to discredit the witness and taint the jury pool - “I barely know Mr. Bloggins. He has always been part of the witch hunt to get me.” The place to state that is in the court room, not on social media.
Sort of like “Nice place you got here. Shame if something happened to it…”
Can this 2 bit criminal throw a wine bottle full of gasoline? Because publicly claiming my GJ testimony is part of a witch hunt would make me a wee bit nervous about going to sleep at night.
Especially when we keep finding witches.
Not at all. There’s too little information in the OP to determine if there was a credible threat. Maybe if the OP told us the nature of his crimes it would be different or Bloggins relation to them it would be different. But “he shouldn’t” on it’s own is not a threat at all.
Traditionally, witness tampering doesn’t require a threat. You could encourage, cajole, beg, plead, sweet talk, implore, or otherwise explain why it would be best if you didn’t participate, and it would be a crime.
Any form of encouragement not to testify is witness tampering.
Here’s the federal statute. The operative language, I’d think, is “corruptly persuades”
None of those are in the OP.
I think the OP turns on whether it was communicated to the witness. A post on social media probably doesn’t cut it. A private text, or a direct message? Yeah.
And what if you know that the person reads yours posts, or what if you don’t communicate to the person but put up a billboard near his house? Well, that’s the weeds in which lawyers live.
If it’s too outrageous or roundabout in a telling way, you’d get in trouble.
“corruptly persuades another person, or attempts to do so”
In the hypothetical, he surely attempted to persuade. But did he do it corruptly?
Ive seen many definitions of “corruptly”.
Oxford has “in a way that is not honest or moral, in return for money or to get an advantage”
Well, in the hypothetical, a reasonable person would concoude that the defendant was attempting to persuade a witness to not testify in a situation where that would assumedly benefit the defendant, which in itself is not an honest or moral act. So it would seem by that definition, the act was done corruptly.
But other definitions Ive seen of corruptly focus more on abusing a position of power for personal gain, or focus on monetary gain, which didnt really happen here.
So its a toss up and I think wed need a professional opinion from someone with direct experience or specific case history examples of similar cases.
The only way I can see this as witness tampering is if there’s a credible concern that you’re issuing a veiled threat when you write “He shouldn’t.” Say, you’re known for sending out goons after people or knowing others to act as goons on your behalf. Otherwise, everything you posted on social media is likely the same as you’d like provide in testimony.
What if there are numerous cases of people committing violence because they thought that you asked them to?
I tried to cover that in my response, but I guess I wasn’t clear.
ETA: I edited the bolded part in to the original post immediately after I posted it, but maybe you didn’t see a refreshed version before you replied.
It’s right there - “to get an advantage”. If the witness’s testimony is likely to the alleged threatener’s disadvantage, then telling him or her - via a widely read public platform or directly - not to testify is corruptly “persuading”, even if it’s a non-threatening ask.