  We review the geometric formulation of the second Noether's theorem in
time-dependent mechanics. The commutation relations between the dynamics on the
final constraint manifold and the infinitesimal generator of a symmetry are
studied. We show an algorithm for determining a gauge symmetry which is closely
related to the process of stabilization of constraints, both in Lagrangian and
Hamiltonian formalisms. The connections between both formalisms are established
by means of the time-evolution operator.
