I have been spotted climbing over a gate by cops before now and questioned, they rang the local surgery to speak to the Dr's house that I was cleaning.
Also early 1 summer morning, on a Sunday morning I was cleaning a big medical center (always do it on a Sunday as no-one around), I was up on the big flat roof doing all the sky lights, had my Ipod on when a copper tapped me on the shoulder, fair nearly shat myself!
On the subject of dogs and gates, I have 2 police dog handlers on my rounds, thought one was out at work one day and started over the gate when I was met by a very angry trained biter, that made me move a bit sharpish.
Advice to all, never climb a gate with a police dog on the other side!!