PETITION FOR WRIT OF MANDATE The petition is denied. The burden is on Petitioner to demonstrate by a preponderance o the evidence that the DMV hearing officer’s findings are not supported by a preponderance o the evidence. Fukuda v City of Angels (1999) 20 Cal. 4th 805, 820. Petitioner has not met tha burden. Petitioner admits that he was offered the choice of a breath or blood test, and that he gav oral consent to a blood test; but he contends that that he was unable to give a knowing an intelligent consent due to a concussion suffered in the accident which preceded his arrest. Th hearing officer’s rejection of this contention is supported by the evidence—specifically the arres report and supplemental report, which indicate that Petitioner was responsive, answered Office Vasquez’ questions, and gave oral consent to a blood test. Petitioner presented no medica evidence to support his contention that he suffered a concussion, or that someone suffering fro a concussion is unable to give