It is little different than say the respect a police officer is given.  

He was quickly and quietly moved out of his previous home in Detroit by Detroit police; they did so because they were quite aware of arecent murder of an 86-year-old Detroiterwho was killed because he was a $20,000 lottery winner.

I had one property in the area where 2 months ago, 6 police cars with gun drawn pointing to the house.

We've begged the police department to set up more patrol drive by's or at least leave a car there.

You can ask If there is a police report that’s how it falls under the domestic violence requirement to let them out of their lease.  

Maybe 10 years ago, the police call me about a domestic dispute at one of my house. 

I had no idea what was going on until we got an order from the township telling us we are not allowed to rent individual rooms and they discovered this was happening due to the police getting called to a disturbance at the house. 

Realistically,  there isn't some 'garbage hauling police squad' monitoring this, so they would likely not get caught.

Think about how your rules affect their rights to carry on the same rights as an owner, which is what you convey by a lease, you can cover illegal activities easily, no business concerns in a residence, pet policies, care of the property, even additional administrative aspects that were not expected when the rents were established, like police calls, neighbor complaints, picking up trash or additional things they cause you to deal with. 

I’ve called the police on several occasions to increase patrol in the area.