A320 FLT CREW REFUSED TO FLY AN ALL-NIGHT SEGMENT FOLLOWING A SHORT DAYTIME LAYOVER.

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FATIGUE DUE TO SCHEDULE MISMATCH DUE SLEEP CYCLE. I RECEIVED THE ASSIGNMENT FOR AN XA30 MST RPT. THE LEG WAS WX DIVERTED TO LAX. AFTER LNDG AT LAX WAS INFORMED OF FERRY FROM LAX AT XQ30 PST. THIS WOULD GIVE APPROX 10 HRS AT THE LAX HOTEL; AND ABOUT 12 HRS ON THE GND IN ZZZ PRIOR TO THE ALL NIGHT LEG OF ZZZ-ZZZ1. I INFORMED THE FLT MGR THAT THIS SHORT LAYOVER AND BACK OF CLOCK SLEEP CYCLE MIGHT BE A FACTOR THE NEXT DAY. THE FERRY FROM LAX-ZZZ WAS UNEVENTFUL AS 1 ACFT WAS REFUSED AND HAD TO WAIT FOR THE REPLACEMENT ACFT. THE FERRY FLT LEFT OVER 2 HRS LATE FROM LAX. UPON ARR AT THE ZZZ LAYOVER I INFORMED THE CREW DESK/FLT MGR THAT WITH THE DEP CURFEW FROM ZZZ THE 9 HR LAYOVER WAS INSUFFICIENT FOR PROPER REST. EVEN THOUGH THIS ASSIGNMENT WAS CONTRACTUALLY 'LEGAL' IT FAILED IN A SAFETY ASPECT OF BEING PREPARED TO FLY ALL NIGHT. THE FOLLOWING MORNING BOTH THE FO AND I REINFORCED THAT WE HAD MADE THE PROPER DECISION ON DECLINING THE FLT. WE CAME TO THE CONCLUSION THAT AN ALL NIGHT FLT FOLLOWING THE SHORT LAYOVER WOULD HAVE BEEN UNSAFE. THE FLT MGR AND CREW DESK WERE BOTH HELPFUL AFTER DECLARING THE FATIGUE FACTOR IN DECLINING THE ASSIGNMENT.