Cal. Gov. Code § 53593

No bond counsel with respect to a new issue of bonds shall also be counsel, with respect to that new issue of bonds, to the underwriter or other initial purchaser of the bonds. This section does not preclude the bond counsel from rendering one or more opinions to the underwriter or purchaser with respect to the bonds, the documents or laws pursuant to which the bonds are issued, the official statement, offering circular, or other disclosure document describing the bonds, or any related matter, if the opinion is rendered as bond counsel and not as counsel to the underwriter or purchaser.