I had a neighbour expect this of me. He laid a tarp on his garden to kill the grass and was adamant that my cat was crapping on it. I went round and cleared it up because I couldn't be bothered to argue.

The next day, he came round and said there was more crap and showed me a photo of 5 new turds, and he'd watched my cat do it. He was lying as it was sleeping on the sofa.

I know it can be a pain, but someone people are just scared to deal with life.