My neighbor's cats keep pooping in my yard. How do I stop it?

I laughed my butt off when you explained how you solved your problem since it was the same thing I was going to suggest minus the trailer park were I live we have an island in the river were a large population of drug dealers and welfare recipiants live the cats are afraid to cross the bridge so once you drop them off they're stuck. I was also thinking buy a gun until you mentioned not wanting to be a snipper. I also thought about anti freeze mixed with tuna.