Legal Question in Technology Law in California

Your question would probably fall into the jurisdiction of the California Public Utilities Commission (CPUC), which traditionally has had the power to regulate intrastate utility services in California, including telephone rates and charges. A legal action would start with lodging an administrative complaint with the CPUC, not going to court, where your suit would be rejected as premature until you had pursued and exhausted your (so-called) administrative remedies. It's also slightly possible that a Federal agency such as the Federal Communications Commission would have initial jurisdiction of this rate dispute. I suggest, however, starting your battle by contacting the CPUC's consumer-complaint staff. Well, perhaps even before that, I would nag AT&T extensively about their "tariff authority" for assessing this charge. My hunch is, to be frank, that the charge IS appropriate and lawful, but I am by no means certain.