California Code, Public Utilities Code - PUC § 99563.1

Notwithstanding the provisions of the Government Code or other laws or statutes, the transit district employer shall make deductions from wages and salaries of its employees upon receipt of authorization for the payment of union dues, fees, or assessments, for the payment of contributions pursuant to any health and welfare plan or pension plan or any other purpose for which deductions may be authorized by employees where the deductions are pursuant to a collective bargaining agreement with a duly designated or certified labor organization.