2-way mirros are obsolete spy tech, as you already know they have easy tells:https://invidious.snopyta.org/watch?v=Z5zUbvtj8NU
You can see through a 2way mirror if your room is darker then the other side. If you put a really powerful work-light up to the mirror so that it illuminates the other side you can probably see through it.
A 2way mirror might just be somebody recycling it as a regular mirror and there is nothing behind it. It could still point towards something fishy going on that is not a government op. It's probably illegal to put 2way mirrors into bathrooms, so if you want to make a fuss, you can make it about legal principles.
These days Spy-agencies probably use little cameras, sometimes they drill small holes in to walls to stick very thin fiber-optic light-guides with a camera at the end through a wall (if they can't get direct access to a room), or they put tiny smartphone camera-modules into light switches, smoke detectors or randomly placed objects. They can use laser microphones that can record voices from great distance via measuring the vibrations on the window glass.
Honestly those spy tools might already be outdated as well, because they might just have hacked your phone. You could make forensic IT your hobby, if you get good enough at it that they might risk detection they probably will move on to another target.
Keep in mind that most conspiracies are boring stuff, not black-ops experiments. Like laundering money for funding spy operations off the government books. If there is deep-state shenanigans going on you're probably just an unwitting extra that got employed to make a front org appear legit. The Horro-fiction plots are less likely.
Also consider other possibilities like corporate espionage, or some kind of mafia organization.
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