  The relativistic spinning particle model, proposed in [3,4], is analyzed in a
Hamiltonian framework. The spin is simulated by extending the configuration
space by introducing a light-like four vector degree of freedom. The model is
heavily constrained and constraint analysis, in the Dirac scheme, is both novel
and instructive. Our major finding is an associated novel non-commutative
structure in the extended space. This is obtained in a particular gauge. The
model possesses a large gauge freedom and hence a judicious choice of gauge
becomes imperative. The gauge fixed system in reduced phase space simplifies
considerably for further study. We have shown that this non-commutative phase
space algebra is essential in revealing the spin effects in the particle model
through the Lorentz generator and Hamiltonian equations of motion.
