  Experiments are planned to improve the sensitivity of mu-e conversion from
the current ~ 10^{-12} to 10^{-16} - 10^{-18}. If the muon (bound to the
nucleus) could be polarised, a spin asymmetry of the final state electron is
sensitive to CP violating phases on lepton flavour violating operators. This is
similar to extracting phases from asymmetries in the final state spin and phase
space distributions of mu to 3e and mu to e gamma.
