  A covariant formulation of spin-dependent deep-inelastic scattering from
nuclei is presented. In the relativistic impulse approximation the inclusive
nuclear cross section is described in terms of the amplitude for forward,
virtual-photon scattering from an off-mass-shell nucleon. The general structure
of the off-shell nucleon hadronic tensor is derived, and the leading behavior
of the off-shell nucleon structure functions computed in the Bjorken limit. The
formalism, which is valid for nucleons bound inside nuclei with spin 1/2 or 1,
is applied to the case of the deuteron.
