I’ll go back and read your post but, I never considered 4th amendment as foundation for the argument.
The are too many laws that direclty deal with this issue.
Most of which I’m familiar with and help my clients comply 2ith, so they are legitimately performing their work as well as mitigating sanctions under the law, pprevnting civil action and giving them direct evidence of their work should either occur.
I have many clients in financial, healthcare and other industries where they are required to record transactions or call centers are a major part of their customer acquisition and support.
I’m in telecom and we advise our clients on wide variety of issues.
You can’t use illegally and unlawfully obtain evidence.
Actually, you can in many situations. The situation you are referring to is the exclusionary rule, which operates under the 4th amendment, and restricts the government, but doesn't apply to private citizens. I was trying to point out, for the edification of those interested in the legal issues, is that the reason the recordings will be excluded from any trial is not that they are "illegally and unlawfully obtained", because a private citizen's illegally obtained evidence can be used in court, but because in the State of California there is a statute that makes undisclosed recordings inadmissible in any proceeding.
Other types of illegally obtained evidence might well be admissible. If the maid stole some papers from Sterling, for example, and in the papers were inflammatory writings of his, or an admission of murder, for example, those documents could be used against him in a civil or criminal case.
Your experience in the telecom industry is most likely in connection with subpoenas in criminal and civil cases. Those are examples of legally obtaining information through lawful process (as opposed to the spy agencies, which take it in violation of the rights of all of us.)