Since you are now substantially limiting someones ability to defend themselves, what are you doing to substantially mitigate the opportunity for crime to occur at your property?

If they are borderline we keep them in a holding pattern and keep scoring/investigating others.No matter how you do it, you need a consistent approach and criteria that is defendable and non discriminatory.Sounds like a good problem to have!

They have also defended it in court several times and the tenant was always removed as speedily as possible.

You'll also be broke because the lawyer to defend you will take A TON because you're a "rich slumlord" now!......................................... 

If the defendant wants to be represented by an attorney, 'before the judge decides the case, the defendant has the right to remove the case to the general district court by completing the Removal to General District Court form on the back of the civil warrant and giving it to the clerk or judge.'

It's amazing how quickly people back down when they realize you're prepared to defend yourself.

And on the other side of it, if you are ever defending yourself against a lawsuit, you want to show that you do things "by the book", and you have to have "a book" to do that. 

My guess is your position will be hard to defend with this type of tenant reaction combined with no written documentation of their consent.  

You want your insurance company to stand to lose as much as possible if you get sued, so they defend you the best.

You need coverage to pay the lawyers to defend you, even if you are innocent.