  We gauge the direct product of the Proca with the Dirac equation that
describes the coupling to the electromagnetic field of the spin-cascade
(1/2,3/2) residing in the four-vector spinor and analyze propagation of its
wave fronts in terms of the Courant-Hilbert criteria. We show that the
differential equation under consideration is unconditionally hyperbolic and the
propagation of its wave fronts unconditionally causal. In this way we proof
that the irreducible spin-cascade embedded within four-vector is free from the
Velo-Zwanziger problem that plagues the Rarita-Schwinger description of
spin-3/2. The proof extends also to the direct product of two Proca equations
and implies causal propagation of the spin-cascade (0,1,2) within an
electromagnetic environment.
