Direct CP violation in semi-leptonic and leptonic decays

We show that direct CP violation in semi-leptonic and leptonic decays can occur in multi-Higgs doublet extensions of the electroweak standard model with flavor changing neutral currents. For pion and lepton decays these $CP$ violating effects cannot be constrained directly by experimental data since up to now the branching ratio of the decays $\pi^-$ and $\mu^-$ have not been measured in laboratory.