We have a problem employee who we found out is recording phone conversations with other employees, including their manager, without knowledge or consent. The employee is in the US state of Georgia, while the people being recorded are in California. I have looked up some of the laws regarding recording in California, Georgia, and Federal, but its a bit confusing. My opinion is that consent is required with any one on one conversation, but am unsure of the legality of these actions?
This document is a handy summary of US laws. The primary distinction is between one-party and all-party consent states. In California, all parties must "consent" to recording, but in Georgia, only one party has to consent. "Consent" can be implicit, so if someone announces that they are recording, consent has been effectively given (that's not a hard and fast rule: you have to look at the actual case law and statutory language for that state, but usually this is covered by the "reasonable expectation of privacy" part of the law, where you don't have a reasonable expectation of privacy if someone announces that they are recording the conversation).
As it happens, there was a case tried in California involving Georgia-to-California calls, Kearney v. Salomon Smith Barney, Inc., S124739 (Sup. Ct. Cal. July 13, 2006), declaring that California law must be obeyed by a person calling into California. The court declined to decide whether a person could be criminally prosecuted for such a violation of the law, but there is possible civil liability.