  Using the CLEO II detector at the $e^+e^-$ storage ring CESR, we have
determined the Michel parameters $\rho$, $\xi$, and $\delta$ in $\tau^\mp \to
l^\mp\nu\bar{\nu}$ decay as well as the tau neutrino helicity parameter
$h_{\nu_\tau}$ in $\tau^\mp \to \pi^\mp\pi^0\nu$ decay. From a data sample of
$3.02\times 10^6$ tau pairs produced at $\sqrt{s}=10.6 GeV$, using events of
the topology $e^+e^- \to \tau^+\tau^- \to (l^\pm\nu\bar{\nu})
(\pi^\mp\pi^0\nu)$ and $e^+e^- \to \tau^+\tau^- \to (\pi^\pm\pi^0\bar{\nu})
(\pi^\mp\pi^0\nu)$, and the determined sign of $h_{\nu_\tau}$, the combined
result of the three samples is: $\rho = 0.747\pm 0.010\pm 0.006$, $\xi =
1.007\pm 0.040\pm 0.015$, $\xi\delta = 0.745\pm 0.026\pm 0.009$, and
$h_{\nu_\tau} = -0.995\pm 0.010\pm 0.003$. The results are in agreement with
the Standard Model V-A interaction.
