Cal. Penal Code § 3060.5

Notwithstanding any other provision of law, the parole authority shall revoke the parole of any prisoner who refuses to sign any form required by the Department of Justice stating that the duty of the prisoner to register under Section 290 has been explained to the prisoner, unless the duty to register has not been explained to the prisoner, or refuses to provide samples of blood or saliva as required by the DNA and Forensic Identification Data Base and Data Bank Act of 1998 (Chapter 6 (commencing with Section 295) of Title 9 of Part 1), and shall order the prisoner returned to prison. Confinement pursuant to any single revocation of parole under this section shall not, absent a new conviction and commitment to prison under other provisions of law, exceed six months, except as provided in subdivision (c) of Section 3057.