There was a time, not too long ago, when the technology related to hidden cameras was such that it using one wouldn't even enter your mind. Such cameras were expensive. They had to be wired up to work. The only people who used them were spies and the police, and then only if they had some sort of warrant. Otherwise, it would violate privacy.
A lot has changed in the tech explosion that we've experienced in the last decade or so. Cameras, hidden or otherwise, have gotten so good and so small that they are now in virtually every cellphone.
That means just about everyone can access the technology, and many have. Witness the appearance of the so-called nanny cams. Family members, concerned about possible nursing negligence when it comes to their loved ones in specialized care facilities, have used them effectively to support criminal and civil actions. Still being debated, however, are the ethical and legal implications of surreptitious surveillance, whether in Pennsylvania, Ohio or anywhere else.