What should concern you most is that they didn't disengage when they were informed that she was a Senate staffer discussing legislative work and in fact seemed very bent on getting details about the legislation in question.
Talking about tear gas in the privacy of one's home is not a crime. If that appliance repairman was the "informant", he should be in jail for wiretapping.
Is that really necessary?
I want the FBI to do their job; I just don't want them to look like and/or be the bad guys. In this situation, they smell like the bad guys.