Sometimes injuries or illnesses can appear much like impairment by alcohol or drugs. A person with a head injury, who causes an accident, may appear to a police officer like a person who is impaired by alcohol or drugs.
In Colorado if a person over 21 is convicted of traffic violations totaling 12 or more points within a 12 month period, or 18 or more points within a 24 month time period, the person's license gets suspended for up to a year due to points accumulation
Before law enforcement is required to advise a person of their rights (i.e. the right to remain silent, the right to consult a lawyer, etc.) two conditions must exist: (1) the person must be "in custody" (reasonably believe they are not free to go) and (2) they must be subject to interrogation (questions designed to elicit an incriminating response).
Recently I have had a number of cases where clients were charged with crimes, one even arrested and jailed overnight, when no crime occurred. Fortunately we were able to convince the prosecutor of that and they dismissed the cases