Off-shell BRS-invariant construction of N=1, D=4 conformal supergravity

A geometrical construction is displayed of the BRS structure of the N=1, D=4 conformal supergravity theory. The requirement of a nilpotent differential structure determines directly the closure of the conformal supergravity transformation laws. All existing geometrical constraints between field strengths are systematically worked out from the requirement of Bianchi identities. As a by-product of the technics involved, some new features of conformal gravity are revealed. (orig.)