Cal. Lab. Code § 227

Whenever an employer has agreed with any employee to make payments to a health or welfare fund, pension fund or vacation plan, or other similar plan for the benefit of the employees, or a negotiated industrial promotion fund, or has entered into a collective bargaining agreement providing for these payments, it shall be unlawful for that employer willfully or with intent to defraud to fail to make the payments required by the terms of that agreement. A violation of any provision of this section where the amount the employer failed to pay into the fund or funds exceeds five hundred dollars ($500) shall be punishable by imprisonment pursuant to subdivision (h) of Section 1170 of the Penal Code, or in a county jail for a period of not more than one year, by a fine of not more than one thousand dollars ($1,000), or by both that imprisonment and fine. All other violations shall be punishable as a misdemeanor.