Gauss Law Constraints in Chern-Simons Theory From BRST Quantization
  The physical state condition in the BRST quantization of Chern-Simons field theory is used to derive Gauss law constraints in the presence of Wilson loops, which play an important role in explicitly establishing the connection of Chern-Simons field theory with 2-dimensional conformal field theory. 
M. Chaichian, W.F. Chen and Z.Y. Zhu