  Quantization of the free and interacting Rarita-Schwinger field is considered
using the Hamiltonian path-integral formulation. The particular interaction we
study in detail is the $\pi N \De$ coupling used in the phenomenology of the
pion-nucleon and nucleon-nucleon systems. Within the Dirac constraint analysis,
we show that there is an excess of degrees of freedom in the model, as well as
the inconsistency related to the Johnson-Sudarshan-Velo-Zwanzinger problem. It
is further suggested that couplings invariant under the gauge transformation of
the Rarita-Schwinger field are generally free from these inconsistencies. We
then construct and briefly analyse some lowest in derivatives gauge-invariant
$\pi N \De$ couplings.
