Before I retired I worked in the HR department at a major company. We once had a situation where an employee was peeing on the chairs of female employees (after hours). We figured he must be hiding in a restroom at the end of the business day, then sneaking out to do his business. We asked Security to put a camera up to catch him. They showed us the camera and a smoke detector housing it would be placed in. Before he was caught a somewhat paranoid employee asked about the new “smoke detector” and said he thought it was a camera. Security had left the smoke detector box above the ceiling tiles. A Facilities employee went up on a ladder and pulled out the box, assuring everyone it was just a smoke detector. The employee who was misbehaving was caught a few days later and fired. And of course it was the employee who was worried about a camera. Bottom line, smoke detector housings are used legitimately all the time to hide a camera. But at times I’m sure they are used by people who do not have a legitimate reason to hide a camera.
What? I have never heard of such a thing. Why would this guy do this? Never mind, don’t tell me. Don’t want to know.