CA Educ Code Section 24617

(a)

To recover an amount overpaid under this part or Part 14 (commencing with Section 26000), the corrected monthly allowance payable under the Defined Benefit Program or benefit payable under the Defined Benefit Supplement Program or the Cash Balance Benefit Program may be reduced by no more than 5 percent if the overpayment was due to error by the system, the county superintendent of schools, a school district, or a community college district, and by no more than 15 percent if the error was due to inaccurate information or nonsubmission of information by the recipient of the allowance or benefit.

(b)

This section does not apply to the collection of overpayments due to fraud or intentional misrepresentation of facts by the recipient of the allowance or benefit.