landlording nightmare

[James S.]

So my father has been a landlord for about 20 years in Detroit, under his wing ive never once heard of a story like this 

Weve had a tenant in a house for about 5 years now, hes a decent tenant and he loved the house  so allowed him to buy the house off of us with a land contract.

about 3 years ago the man decides to turn to a life of crime.
this tenant heard about one of my father's units being destroyed, he said to my father " i know who did it and ill take care of it"
the person who supposedly gutted our apartment ended murdered shortly after. the tenant claimed responsibility for it. 

at this point fearing for our lives we call the police on him, we tell them we are very sure he is selling drugs and this man is dangerous. 
the Detroit police watch him like a hawk, they raid the house and indeed find several amounts of cocaine and prescription meds. somehow the city lets him go, now the tenant is erratic with the payments. my father tries to confront him about the payments, this tenant somehow knows where our other business is located and tells him if he ever tries to evict, he will shoot us dead. 

since the first raid the police have raided the house and pulled him over several times, each time finding drugs in his possession each time getting let go. this last time we got a letter from the city of detroit ordering us to evict this tenant, we ask the police for help and  unfortunately we got nothing. the major of Detroit himself sues us and shows up to court, he makes a statement that it is our responsibility to take care of the "nuisance" and not the responsibility of the city 

with the city refusing to help and instead telling us to evict or they will take the home. my father has decided to let the home fall into tax foreclosure. the house is worth 20-35k defiantly not worth anyone's life.