CTLR ISSUED A DSCNT CLRNC TO ACFT Z. ACFT X READ BACK CLRNC AND STARTED DSCNT; WHICH NOW BECAME TFC FOR ACFT Y. CTLR MISSED THE READBACK FROM WRONG ACFT. LATER; CTLR ATTEMPTED TO SEPARATE ACFT X FROM ACFT Y; TOO LATE; LOST LEGAL SEPARATION.

Narrative

A THIRD ACFT WAS INVOLVED; AN SF34 (ACFT Z). I DSNDED THE SF34 FROM 11000 FT TO 8000 FT AND THE E120 (ACFT X) READ BACK AND COMMENCED THE DSCNT. I MISSED THE READBACK. I WAS FOCUSED ON AN UNTAGGED TARGET THAT WAS TFC FOR THE SF34 AND ANOTHER TFC SIT ON MY SCOPE. AS I WAS SCANNING MY SCOPE; I OBSERVED THE E120 (ACFT X) IN A DSCNT THAT WOULD CONFLICT HEAD-ON WITH THE PA28 (ACFT Y). I 'BROKE IN' TO THE FREQ AND TOOK EVASIVE ACTION WITH THE E120 (ACFT X) AND THE PA28 (ACFT Y). AT NO TIME DID THE CONFLICT ALERT ACTIVATE. IT IS UNKNOWN IF THE E120 (ACFT X) RECEIVED A TCASII RESOLUTION. I CALLED MY SUPVR AND ALERTED HIM TO THE SIT. I WAS RELIEVED OF DUTIES AND AN INVESTIGATION WAS STARTED. THERE WERE NO OTHER WITNESSES BESIDES MYSELF AND I NEVER STATED THAT I LOST IFR SEPARATION. BASED UPON THE AUDIO TAPE; THE SIT WAS AND IS CLASSIFIED AS AN OPERROR. WITH OUR NEW ARTS 3E EQUIP; THERE IS NO LONGER THE CAPABILITY TO PERFORM A DATA RESOLUTION OR ACTUALLY CHART THE ACFT. MY FACILITY TRIED TO DEMONSTRATE THAT I DID NOT LOSE IFR SEPARATION; HOWEVER; THE WESTERN PACIFIC REGIONAL OFFICE REFUSED TO OVERTURN BECAUSE WE COULD NOT 'PROVE' BEYOND A 'SHADOW OF A DOUBT' THAT WE DID NOT LOSE IFR SEPARATION. THIS RULING AGAINST ME -- ALSO REALLY ANYONE ELSE THAT COULD BE CAUGHT IN A SIMILAR SIT -- DEFIES ALL LOGIC! COULD SOMEONE PLEASE INVESTIGATE?