Earlier quoted context omitted.
It is so ridiculous that the comment for a payment would be used against someone. Writing jokes in the 'for' line on a check is a time honored tradition when paying your friends money. I don't want to live in a world where I am not allowed to make jokes because it might get me a visit from the FBI.
Why is it important to put jokes there? I view a check as a pseudo-legal document. Do you slip jokes into the contracts you sign?
Yeah, it's juvenile. I don't understand why the FBI would care though. There's a 0% chance that a real terrorist is writing "ISIS" on their checks to fund terror.