  The Hamiltonian analysis for the Chern-Simons theory and Pontryagin
invariant, which depends of a connection valued in the Lie algebra of SO(3,1),
is performed. By applying a pure Dirac's method we find for both theories the
extended Hamiltonian, the extended action, the constraint algebra, the gauge
transformations and we carry out the counting of degrees of freedom. From the
results obtained in the present analysis, we will conclude that the theories
under study have a closed relation among its constraints and defines a
topological field theory. In addition, we extends the configuration space for
the Pontryagin theory and we develop the Hamiltonian analysis for this modified
version, finding a best description of the results previously obtained.
