I have neighbors involved in a dispute. I had a private conversation with one of the neighbors outside of their home. The other neighbor called me later that day to tell me that he'd been told of the conversation that I had with the first neighbor and that he has ways of knowing about these things. I do not know what "ways" he has, but given his background I suspect that he might be using survelliance equipment.

Are his actions legal? If not, what recourse do I have?