Air Traffic Control Fully Certified
Other / Unknown
Inflight Event / Encounter Weather / Turbulence
Flight Crew Took Evasive Action
Weather
There was a rapidly closing gap between two large areas of precipitation on the east and west sides of my sector. Aircraft X called and asked for 35;000 FT. I told Aircraft X that there was traffic off the left wing and to their 12 o'clock; both deviating through the same weather that Aircraft X was in. Aircraft X reiterated that they needed lower and I called traffic on the 737 at their 12 o'clock; asking them to wait two minutes. They then said that they had to descend now; and I told them that I could not authorize a descent. Aircraft X then descended to 35;000 FT; and Conflict Alert went off. I asked Aircraft X if they were declaring an emergency; and they said yes. I asked them if they could hold at 35;000 FT; because I didn't know why they were descending and there was additional traffic ahead at 27;000 FT. I then handed off Aircraft X and switched them to the Wilmington-35 controller's frequency. The pilot made a decision based on factors that they didn't share with me; and I told them repeatedly that I could not authorize their descent.
ZDC Controller described a loss of separation event when traffic descended without clearance during multiple weather deviations.