  Energy and angular distributions of the tau decay products in the
CERN-to-Gran Sasso $\nu_\tau$ appearance experiments are studied for the decay
modes $\tau\to\pi\nu$ and $\tau\to l\bar\nu\nu$ (l=e or mu). We find that the
decay particle distributions in the laboratory frame are significantly affected
by the tau polarization. Rather strong azimuthal asymmetry of $pi^-$ and $l^-$
about the tau momentum axis is predicted, which may have observable
consequences even at small statistics experiments.
