  The $B-L$ MSSM is the MSSM with three right-handed neutrino chiral multiplets
and gauged $B-L$ symmetry. The $B-L$ symmetry is broken by the third family
right-handed sneutrino acquiring a VEV, thus spontaneously breaking $R$-parity.
Within a natural range of soft supersymmetry breaking parameters, it is shown
that a large and uncorrelated number of initial values satisfy all present
phenomenological constraints; including the correct masses for the $W^{\pm}$,
$Z^0$ bosons, having all sparticles exceeding their present lower bounds and
giving the experimentally measured value for the Higgs boson. For this "valid"
set of initial values, there are a number of different LSPs, each occurring a
calculable number of times. We plot this statistically and determine that among
the most prevalent LSPs are chargino and neutralino mass eigenstates. In this
paper, the $R$-parity violating decay channels of charginos and neutralinos to
standard model particles are determined, and the interaction vertices and decay
rates computed analytically. These results are valid for any chargino and
neutralino, regardless of whether or not they are the LSP. For chargino and
neutralino LSPs, we will-- in a subsequent series of papers --present a
numerical study of their RPV decays evaluated statistically over the range of
associated valid initial points.
