Small Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 4
Distraction; Situational Awareness
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Requested ATC Assistance / Clarification
Human Factors; Airspace Structure
Aircraft X was inbound to EKO. I issued a descent clearance to 14;000 feet and asked the pilot if he had the weather at EKO and to expect a visual approach. The pilot said he was unable to obtain the weather; so I issued him the current METAR. I also informed the pilot of the airport's location. Moments later; I observed the pilot descending. I immediately issued a low altitude alert since he was in a 13400 ft. MIA (Minimum IFR Altitude) and was descending below. The pilot immediately canceled IFR.
ZLC Center Controller reported an aircraft descended below the assigned altitude and flew below the Minimum IFR Altitude.