Verified answer

I actually did. He could see me at my computer via a mirror on my wardrobe door. I stood up walked a couple of steps away and he was trying to see what was on my screen. I then walked through my garage and stood right where we could see each other. He looked at me with my arms folded. I said nothing to him. I went back and took down the mirror, broke it and placed it up against the wall to my garage right where he could see it. I left it there for weeks so there's no way he would not have seen it. Now I wonder how long he'd been doing that before I caught him out. 

I would confront them over it if I felt it called for it.

My closest neighbour is five miles away, so I don't think that's going to happen.

I guess put on a show they won’t ever forget lol