  We propose a gauge theory of gravitation. The gauge potential is a connection
of the Super SL(2,C) group. A MacDowell-Mansouri type of action is proposed
where the action is quadratic in the Super SL(2,C) curvature and depends purely
on gauge connection. By breaking the symmetry of the Super SL(2,C) topological
gauge theory to SL(2,C), a spinor metric is naturally defined. With an
auxiliary anti-commuting spinor field, the theory is reduced to general
relativity. The Hamiltonian variables are related to the ones given by
Ashtekar. The auxiliary spinor field plays the role of Witten spinor in the
positive energy proof for gravitation.
