When I placed some cut lemons in front of the door I swear that this cat would use them for spraying target practice.

I relented and bought sensor device for the front door. I have also sprayed the first step with some anti dog/cat spray. For part of the back yard where the cat tried and failed to bury it's business I have closed one of the picket fence gates. They other fences may be too high to hurdle. So far so good.

Have to say that I do feel sorry for the cats as they doesn't seem to have much protection from the elements.