The three dimensional Palatini theory plus a Chern-Simons term [PCS] is
analyzed by using the Hamilton-Jacobi [HJ] framework. We report the complete
set of $HJ$ Hamiltonians and a generalized $HJ$ differential from which all
symmetries of the theory are identified. Moreover, we show that in spite of PCS
Lagrangian produces Einstein's equations, the generalized $HJ$ brackets depend
on a Barbero-Immirzi like parameter. In addition we complete our study by
performing a canonical covariant analysis, and we construct a closed and gauge
invariant two form that encodes the symplectic geometry of the covariant phase
space.