What does 'a reasonable expectation of privacy' mean?

What does 'a reasonable expectation of privacy' mean?

Danno Hanks (Private Investigator) gives expert video advice on: What are the legal responsibilities of a private investigator?; What can a private investigator expect when testifying in court?; What does 'a reasonable expectation of privacy' mean? and more...

To any person, expect that you're in a private location. A good way of saying it is if you walk into the bathroom stall. You should have a reasonable expectation that there's no hidden video equipment in the bathroom stall. There's no recording devices in there. That's a reasonable expectation of privacy. If you're in your home and you've closed your curtains up, even though somebody could walk up and peek through the curtain, you have a reasonable expectation of privacy. If you're in a public place where anybody walking by can see you or hear you, you do not have a reasonable expectation of privacy. That's the bottom line.