ACR X CLBED TO WRONG ALT.

Narrative

AFTER TKOF FROM DFW; WE FLEW ASSIGNED HDG 240 DEG AND ALT 2000 FT MSL. AFTER CONTACTING DEP CTL WE WERE GIVEN 'FLY HDG 230 DEGS; CLB AND MAINTAIN 3000 FT; TFC AT 2 O'CLOCK DSNDING TO 4000 FT.' ONCE CLR OF TFC DEP SAID 'TFC NO FACTOR; CLB AND MAINTAIN 12000 FT AND FLY HDG 170 DEG.' WE READ BACK 'CLB AND MAINTAIN 12 -- 12000 FT; FLY HDG 170 DEGS;' THEN SET THE ALT SELECTOR AND CONFIRMED THE ALT WITH EACH OTHER. AFTER LEVELING AT 12000 FT DEP SAID 'ARE YOU LEVEL AT 11000 FT;' WE REPLIED 'NO; YOU GAVE US 12000 FT;' HE REPLIED; 'NO; I GAVE YOU 11000 FT; WE NEVER GIVE YOU 12000 FT OUT OF HERE;' WE REPLIED 'WE READ BACK 12000 FT;' HE REPLIED 'I'M NOT WORRIED ABOUT WHAT YOU READ BACK; I GAVE YOU 11000 FT.' WE REPLIED 'DO YOU WANT US TO STAY AT 12000 FT OR DSND TO 11000 FT;' HE SAID 'I WANT YOU AT 11000 FT; DSND AND MAINTAIN 11000 FT.' LOOKING BACK AT THE SIT; WHEN WE WERE ASSIGNED 12000 FT WE THOUGHT THAT 12000 FT WAS UNUSUAL FOR A SW DEP. (NORMAL FOR A SW DEP WOULD BE 11000 FT; WHEREAS 12000 FT WOULD BE NORMAL FOR A NE DEP). WE SHOULD HAVE QUERIED THE CTLR ABOUT THE ASSIGNED ALT. ON THE OTHER HAND; THE CTLR WAS VERY DEFENSIVE WHEN WE SAID WE WERE GIVEN 12000 FT. WHEN WE SAID 'WE READ BACK 12000 FT;' HIS ATTITUDE WAS SUCH THAT OUR READBACK MEANT NOTHING TO HIM. WE FEEL THE READBACK IS CONFIRMATION FOR BOTH PARTIES. FINALLY; WE HAD TO QUERY THE CTLR AS TO WHETHER HE WANTED US TO REMAIN AT 12000 FT OR DSND TO 11000 FT. HE MADE NO EFFORT TO CORRECT THE MISTAKE WITHOUT BEING PROMPTED.