Any Unknown or Unlisted Aircraft Manufacturer
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 5
Training / Qualification; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued New Clearance
Procedure; Human Factors; Airspace Structure
I was not personally involved but heard and observed some of the event as it was taking place.  There was training on the Radar Assist and Radar at the sector.  A departure was in conflict with an arrival to the same airport.  The instructor told the departure to turn to the north below the Minimum IFR Altitude.  I would not normally have been aware of the situation except the instructor was having a discussion with student about the safest remedy to the situation which caught my attention.  There was also a Supervisor monitoring that sector; but I'm not sure if they actually saw what happened or even know that an error occurred.About 30 minutes later I heard another discussion taking place about another aircraft below the Minimum IFR Altitude (MIA).  When I looked at the sector there was a slow aircraft departing Approach's airspace to the north.  The aircraft was at 8;000 feet in a 9; 500 MIA.  I don't know any more details about that aircraft.
ZSE Center Controller reported they observed another sector Controller vector an aircraft that was in confliction with another aircraft below the Minimum IFR Altitude. Later the reporter observed another aircraft in that sector below the Minimum IFR Altitude.