B737-700
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 3
Confusion
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Returned To Clearance
Human Factors
I was working final for roughly 40 minutes and the rush was winding down. The last four or five arrivals all came in on the TELLR Arrival and all but one was cleared for the ILS to Runway 35L off of the TELLR Arrival. The only one that wasn't was vectored. Aircraft X was the fourth one in the string of TELLR's and was cleared the same way every other plane was cleared and was issued traffic that would be underneath them at 10;000 FT for the west complex runways. Aircraft X was observed vacating 11;000 FT; which is the altitude he should've been at until CRUUP on the localizer for that runway; so I issued a climb to 11;000 FT and a heading of 010 to intercept the localizer. When Aircraft X was quizzed about what happened and why they were at an altitude they were leaving the altitude that they shouldn't have been; Aircraft X responded that they were responding to a TCAS RA. Aircraft X was then issued the Brasher. I don't really have a recommendation other than we should expect more from the pilot's tasked with flying numerous people all over the world. This situation should never happen since the airplane is flying an RNAV route and RNAV is designed to separate airplanes.
Denver TRACON controller reported a loss of separation when an aircraft on a RNAV route descended below a crossing restriction; responding to a RA for traffic the restriction was in place for.