RWY INCURSION AFTER LNDG.

Narrative

WE HAD JUST LANDED OUR CITATION ON RWY 24R AT LAX AND WE WERE TOLD TO 'TURN L ON THE REVERSE HIGH-SPD TXWY; HOLD SHORT OF RWY 24L; STAY ON THE TWR FREQ.' I WAS THE ASSIGNED CAPT BUT WAS IN THE R SEAT AS PNF AND I READ BACK THE CLRNC INCLUDING THE 'HOLD SHORT' INSTRUCTIONS. THE FO TAXIED CLR OF RWY 24R ON THE TXWY ASSIGNED AND TAXIED BEYOND THE RWY 24L HOLD SHORT LINE. I NOTICED THAT WE HAD TAXIED PAST THE HOLD SHORT LINE AND I TOLD THE FO THAT WE NEEDED TO STOP NOW! WE STOPPED IMMEDIATELY AFTER THAT. WHEN WE HAD COME TO A STOP WE WERE WELL BEYOND THE HOLD SHORT LINE BUT STILL ABOUT 80-150 FT SHORT OF THE N EDGE OF RWY 24L. I HAD BEEN DISTR INITIALLY BY THE NEED TO FIND THE REVERSE HIGH-SPD TXWY ON THE ARPT DIAGRAM IN ORDER FOR US TO CLR RWY 24R AS INSTRUCTED. I THEN ALLOWED MYSELF TO BE MOMENTARILY DISTR BY LOOKING AT THE ARPT DIAGRAM TO PLAN AHEAD THE DIRECTION OF OUR NEXT TURN AFTER WE CLRED RWY 24L. WHEN I LOOKED BACK UP; I DID NOT SEE THE HOLD SHORT LINE AHEAD OF US AND I REALIZED THAT WE MUST HAVE PASSED IT. I BELIEVE THAT IT WAS AT THAT SAME TIME THAT THE FO ALSO REALIZED THAT WE MUST HAVE PASSED THE HOLD SHORT LINE. WHEN WE CAME TO A STOP SHORT OF THE RWY; A BOEING 737 HAD ALREADY STARTED HIS TKOF ROLL ON RWY 24L. MY FO AND I HAD INDEPENDENTLY MADE THE ANALYSIS THAT SAFETY WAS NOT COMPROMISED BY OUR POS CLOSER TO THE RWY EDGE THAN NORMAL. THE BOEING 737 ON RWY 24L COMPLETED HIS TKOF AND WE WERE THEN CLRED TO TAXI ACROSS RWY 24L. SOMEONE; PROBABLY 1 OF THE 737 PLTS; COMMENTED ON THE TWR FREQ THAT THE AIRPLANE HOLDING SHORT OF THE RWY HAD BEEN 'WELL PAST THE HOLD SHORT LINE.' THERE WERE NO FURTHER DISCUSSIONS OF THIS INCIDENT (RADIO OR OTHERWISE) THAT I KNOW OF EXCEPT BTWN MY FO AND ME.