There is established a plan to be known as the "payroll savings plan" by means of which state and parish employees may purchase United States series "EE" bonds from their monthly earnings through an approved payroll system. Under this plan the employees may authorize the department by which they are employed to deduct and withhold any part of their monthly earnings for the purchase of bonds in such denominations as they may determine; but no deduction shall be made from the earnings of any employee for the purchase of bonds unless the deduction is specifically and voluntarily authorized in writing by the employee.
La. Public Officers and Employees § 42:451