Cal. Rev. & Tax. Code § 41024

Every service user in this state is liable for the surcharge until it has been paid to this state, except that payment to a service supplier registered under this part is sufficient to relieve the user from further liability for the tax.

Any surcharge collected from a service user which has not been remitted to the board shall be deemed a debt owed to the State of California by the person required to collect and remit such surcharge. Nothing in this part shall impose any obligation upon a service supplier to take any legal action to enforce the collection of the utility users surcharge imposed by this part. The service supplier shall provide the board with amounts uncollected which total three dollars ($3) or more on a cumulative basis with respect to a single service user along with the names, addresses and reasons of the service users refusing to pay the surcharge imposed by this part.