How many times have seen ignorant landlord posts on this form asking if it's OK to discriminate against non-protected classes, and then a number of equally ignorant people responding that "no you cant discriminate against pit bulls, rapists, and people threatening to beat you up because that's "discrimination" as if that's prima facie illegal.. 

I've learned that even though @Cameron Norfleet was asking a question without stating his opinion, someone can threaten to publish it against his firm... and lastly, I've learned that even if a landlord hasn't discriminated, his ignorance can still be shown.

They hated the situation too, and therefore they threatened to call the loan.  

Anyways a couple of days ago the cops were called because the boyfriend was over the house and caused a scene, threatening my tenant and waking up the other two units at 1AM. 

I ignored my gut feelings and sure enough when November came, she got into a big row with the upper tenant and threatened her with violence. 

., and I was able to (all times but once) just talk in a friendly manner, and simply lay out the facts, without sounding threatening - if that makes sense. 

Maybe you threaten with that to get her to move.

As long as they aren't threatening in any way, I would chalk it up to personality differences and be prepared for it moving forward.Just my 2 cents.

The tenants were on vacation, and a neighboring tenant called the police saying her boyfriend was threatening her with a gun.

If the tenant does not feel threatened, they will be more likely to cooperate.