One of the challenges of developing Silicon-based spintronics technology is developing non-destructive methods for characterizing spin-polarized conduction electrons. Si is indirect bandgap and optical magneto-optical methods don't work. We have demonstrated that laser-injected spin-polarized electrons enhance the spin-relaxation of bound Mu- in GaAs. The goal of the proposed experiment is to demonstrate the ability of MuSR to detect spin-polarized electrons in Si and an indirect bandgap semiconductor for the first time, thus opening the possibility for MuSR to contribute uniquely to semiconductor spintronics research. A 10 ns duration UV pump pulse tuned to the spin-polarization resonance will inject spin-polarized electrons in bulk Si and the HI Field muon spectrometer field-tuned to the avoided level crossing resonance of various Mu species in Si will probe laser-induced changes.