California Code, Vehicle Code - VEH § 21061

(a) In addition to any action prescribed in Division 17 (commencing with Section 40000.1), a traffic officer may issue a notice of reexamination to any person who violates any provision of this division and who, at the time of the violation, exhibits evidence of incapacity to the traffic officer which leads the traffic officer to reasonably believe that the person is incapable of operating a motor vehicle in a manner so as not to present a clear or potential danger of risk of injury to that person or others if that person is permitted to resume operation of a motor vehicle.

(b) For purposes of this section, “evidence of incapacity” means evidence, other than violations of this division, of serious physical injury or illness or mental impairment or disorientation which is apparent to the traffic officer and which presents a clear or potential danger or risk of injury to the person or others if that person is permitted to resume operation of a motor vehicle.