ACR LTT LEVELED OFF AT INTERMEDIATE ALT CAUSING POTENTIAL CONFLICT AIRBORNE.

Narrative

WE WERE ALREADY IN A DSCNT FROM 10000 TO 8000' WHEN APCH RECLRED US TO CONTINUE THE DSCNT TO 6000'. THE CAPT; WHO WAS FLYING THE ACFT ON AUTOPLT; DID NOT DSND PAST 8000'. AS WE BEGAN THIS FLT THE CAPT WAS IN A NOT SO GOOD A MOOD. EARLY MORNING; LATE ARR; ARGUMENTS WITH THE STATION MGR AND A VERY ABRASIVE AND INTIMIDATING ATTITUDE TOWARDS MYSELF. AT THIS POINT IN THE FLT THE CAPT WAS FLYING THE ACFT VIA THE AUTOPLT IN A DSCNT. I TOLD THE CAPT I WAS GOING OFF 1 TO CALL COMPANY ON #2. AT THE SAME TIME APCH CALLED AND RECLRED US TO A LOWER ALT OF 6000'. AS I SCANNED THE FLT INSTRUMENT I DIALED IN 6000' ON THE ALT PRESELECT AND NOTICED THE AUTOPLT ATTEMPTING TO LEVEL OFF AT 8000' WITH A 250' FPM RATE OF DSCNT. I LOOKED AT THE CAPT AND SAID; 'OK; NOW I'M OFF 1 TO CALL COMPANY ON 2 AGAIN.' HE ACKNOWLEDGED WITH A STATEMENT; 'FINE; KNOCK YOURSELF OUT.' NOW AS I WAS ON #2 RADIO I NOTICED THE CAPT OFF #1 AND ON THE P/A. NEXT I NOTICED; AS I CAME BACK ON #1; THAT THE CAPT HAD NOT DSNDED TO 6000'. WE WERE LEVEL ON AUTOPLT AT 8000' AND APCH WAS CALLING FOR US TO DSND IMMEDIATELY TO 6000' FOR CONFLICTING TFC. THE CAPT ALSO CAME BACK ON AND HEARD THE CALLS. WE DSNDED TO 6000' AND THE CAPT YELLED AT ME TO KEEP MY EARS OPEN AND SO ON. I DECIDED NOT MAKE AN ARGUMENT WITH HIM SENSING IT WOULD FURTHER ENDANGER THE FLT AS WE ENTERED THE TERMINAL AREA AND WORK LOAD WAS INCREASING. I WANTED TO PUNCH OUT THE CAPT AT FIRST FOR THE WAY HE TREATED ME AND THE FLT. I CALMED MY SELF DOWN AND CONCENTRATED ON DOING MY JOB; EVEN THOUGH I KNEW THERE WOULD BE A LESSER DEGREE OF SAFETY DUE TO THE CAPT'S ATTITUDE. I LEARNED AGAIN NOT TO RELAX MY SCAN; EVEN WHEN FLYING WITH A GUY WHO WAS AS INTIMIDATING AS THIS ONE. I'LL ALWAYS SPEAK UP.