It is in california, among other places. Federally, there are about 5 or 6 regulations covering workplace speech, the most sweeping of which is usually consider

It is in california, among other places. Federally, there are about 5 or 6 regulations covering workplace speech, the most sweeping of which is usually considered to be the NLRA. If you google for nlra and lexology, you can see a number of articles about the scope.