Cal. Rev. & Tax. Code § 19705
(a) Any person who does any of the following shall be guilty of a felony and, upon conviction, shall be fined not more than fifty thousand dollars ($50,000) or imprisoned pursuant to subdivision (h) of Section 1170 of the Penal Code, or both, together with the costs of investigation and prosecution:
(5) In connection with any settlement under Section 19442, or offer of that settlement, or in connection with any closing agreement under Section 19441 or offer to enter into that agreement, or compromise under Section 19443, or offer of that compromise, willfully does any of the following: