  The proof of the fact that there are no nontrivial, consistent
cross-couplings that can be added between the Weyl graviton and the massless
Rarita-Schwinger field is accomplished by means of a cohomological approach,
based on the deformation of the solution to the master equation from the
antifield-Becchi-Rouet-Stora-Tyutin (BRST) formalism. The procedure developed
here relies on the assumptions of locality, smoothness, (background) Lorentz
invariance, Poincare invariance, and preservation of the number of derivatives
with respect to each field (the last hypothesis was made only in antighost
number zero).
