The Collaborative International Dictionary of English v.0.48:

Culpability \Cul`pa*bil"i*ty\ (k?l`p?-b?l`?-t?), n.; pl.
   Culpabilities (-t?z). [Cf. F. culpabilit['e].]
   The state of being culpable.
   [1913 Webster]

WordNet (r) 3.0 (2006):

culpability
    n 1: a state of guilt [syn: blameworthiness, culpability,
         culpableness]

Moby Thesaurus II by Grady Ward, 1.0:

29 Moby Thesaurus words for "culpability":
   arraignability, arraignableness, blameworthiness, bloody hands,
   burden, censurability, censurableness, chargeability, complicity,
   criminality, dirty hands, fault, guilt, guiltiness,
   guilty conscience, impeachability, impeachableness, implication,
   inculpation, indictability, indictableness, involvement, onus,
   peccancy, red-handedness, reprehensibility, reproachableness,
   reprovability, reprovableness