We study the minimal gauged U(1)_{B-L} supersymmetric model and show that it
provides an attractive theory for spontaneous R-parity violation. Both
U(1)_{B-L} and R-parity are broken by the vacuum expectation value of the
right-handed sneutrino (proportional to the soft SUSY masses), thereby linking
the B-L and soft SUSY scales. In this context we find a consistent mechanism
for generating neutrino masses and a realistic mass spectrum, all without
extending the Higgs sector of the minimal supersymmetry standard model. We
discuss the most relevant collider signals and the connection between the Z'
gauge boson and R-parity violation.Comment: 4 pages, new title, to appear in Physical Review Letter