As long as the ease dropper owns the company and all the property, should be legal (I am not a lawyer though). Definitely not acceptable by today's ethical standards, but accomplish-able. I would say however that while this person may be able to prove one thing through this, after that, it will be useless because everyone will know it is in use. Get a web cam with audio or something. People legally need to be informed if they are being recorded in most situations. Why should the phone system do this? It is simply a strange request that other industries have addressed, so consult them.