Utah Code Title 53. Public Safety Code § 53-3-302. Definitions

(3)(a) “Impaired person” means a person who has a mental, emotional, or nonstable physical disability or disease that may impair the person's ability to exercise reasonable and ordinary control at all times over a motor vehicle while driving on the highways.

(b) “Impaired person” does not include a person having a nonprogressive or stable physical impairment that is objectively observable and that may be evaluated by a functional driving examination.