What is a license holder's duty to respond to an administrative agency's application to revoke a license?

"When an administrative agency initiates an action to suspend or revoke a [driver's] license, the burden of proving the facts necessary to support the action rests with the agency making the allegation. Until the agency has met its burden of going forward with the evidence necessary to sustain a finding, the licensee has no duty to rebut the allegations or otherwise respond. [Citations.]" (Daniels v. Department of Motor Vehicles (1983) 33 Cal.3d 532, 536, 189 Cal.Rptr. 512, 658 P.2d 1313.)