Most standard leases stipulate the tenant is responsible for any citations issued to the owner due to the tenants' behavior.  

But, the gossipy behavior and asking the tenants if one of them sent the email, etc., was really immature, in my opinion.  

@Christine Swaidan,Check with your attorney about whether you can ask for verification of the second dog as a service animal.That said, it is possible that one dog was trained to help, for example, a limited vision person operate "independently" (trained to focus on the person's surroundings and alert on perceived dangers) while other dog is trained specifically for either emotional support or for some other condition like detecting when the person is in danger of falling into diabetic coma or some kind of seizure (trained to focus on the person and their behavior without being distracted by the person's surroundings).My $0.02...David J Dachtera

I said I wouldn't file this week.Also the reality is the notice to pay move is to reel them back in because they have gotten out of control on rent and other behavior.

Screen well and screen for behavioral issues and abuse of phone numbers should be a relatively rare event.

In credit granting, which is what you are doing in giving them your unit and trusting them to pay each month, the best guide to future behavior is past behavior.

In duplexes we find more established individuals/families, while in buildings with more units we see more transient behavior.  

A better movie for this topic is "Pacific Heights", where Michael Keaton's character makes a rent pre-payment (and engages in some disturbing behavior as well).

I talked to the tenant I expressed my concerns about the situation and their behavior and the safety of the tenant on the first floor and the neighbors who live next door.  

When he doesn't get it from the next guy he damages the house or leaves a big water bill or some such behavior and a bad tenant is born.