California Code, Government Code - GOV § 84104

It shall be the duty of each candidate, treasurer, principal officer, and elected officer to maintain detailed accounts, records, bills, and receipts necessary to prepare campaign reports, to establish that campaign reports were properly filed, and to otherwise comply with the provisions of this chapter.  The detailed accounts, records, bills, and receipts shall be retained by the filer for a period specified by the Commission.  However, the Commission shall not require retention of records for a period longer than the statute of limitations specified in Section 91000.5 or two years after the adoption of an audit report pursuant to Chapter 10 (commencing with Section 90000), whichever is less.