Cal. Pub. Util. Code § 785.2

The commission shall investigate, as part of the rate proceeding for any gas corporation, impediments to the in-state production and storage of natural gas. The commission may adopt a tariff that encourages in-state production or storage of natural gas, including, but not limited to, reducing local transmission rates applicable to in-state gas blends, unless the commission finds that adopting the tariff will likely result in consequences adverse to the interests of gas customers.