
Quoting
adjusterjack
Of course it's legal. No crime here. No law preventing it.
Might be breach of a company policy. Might not be if there was no company policy.
The employee apparently has keys and access and the executives didn't bother to lock up what they wanted to keep private. Ergo, no privacy rights if you don't take even the simplest precautions.
If you are smart, you'll fire this employee right now (by phone, email, and letter) and change the locks immediately so he/she can't get in.
Non-profit has nothing to do with anything.