MLG CROSSED AN ACTIVE RWY WITHOUT CLRNC.

Narrative

AFTER LNDG ON RWY 34; THE TWR CLRED US TO TURN L AT THE END OF THE RWY. THE FO ACKNOWLEDGED. I WAS AT THE CTLS. WE TURNED OFF AT THE END OF THE RWY ONTO TAXIWAY QUEBEC AND CLRED THE ACTIVE RWY; BY DOING SO WE ALSO CROSSED THE END OF RWY 02. AS WE PROCEEDED ACROSS THE END OF RWY 02 I LOOKED DOWN THE RWY JUST TO CHK FOR POSSIBLE TFC; AND I NOTICED THAT AT THE VERY BEGINNING OF THE RWY THERE WAS EITHER A VEHICLE OR AIRPLANE BUT AT THAT DISTANCE I WASN'T SURE IF IT WAS MOVING OR NOT. AFTER XING THE RWY I LOOKED AGAIN AND NOTICED IT WAS AN AIRPLANE ROLLING OUT AND SLOWING DOWN AFTER MAKING A LNDG OR TAXIING ON THE RWY OR WHATEVER. I TURNED TO THE FO AND ASKED IF HE HAD ACKNOWLEDGED ANY HOLD SHORT INSTRUCTIONS FROM THE TWR AND HE SAID 'NO;' AND I KNOW I DIDN'T HEAR ANY HOLD SHORT INSTRUCTIONS. AT THAT TIME THE TWR CAME ON AND SAID; 'WE GAVE YOU HOLD SHORT INSTRUCTIONS' BUT WE; MY FO AND I DIDN'T ACKNOWLEDGE IT AND DIDN'T READ IT BACK TO THE TWR. THE TWR ASKED THE PLT OF THE OTHER AIRPLANE ON THE RWY IF HE HAD ANY PROBLEMS WITH US XING AT THE END AND HE REPLIED 'NONE WHATSOEVER.' I CALLED THE TWR SUPVR AND DISCUSSED THE SITUATION AND HE INFORMED ME THAT NO FURTHER ACTION NEEDED TO BE TAKEN OR DISCUSSED. MY RECOMMENDATIONS CONCERNING THIS MATTER IS THAT HOLD SHORT OF RWYS AFTER LNDG CLRNC MUST BE ACKNOWLEDGED AND REPEATED BY BOTH PLTS AND CTLRS TO BE SURE THE CLRNC IS RECEIVED AND UNDERSTOOD.