Using a sample of 4.7 fb(-1) integrated luminosity accumulated with the CLE
O II detector at the Cornell Electron Storage Ring (CESR), we investigate t
he mass spectrum and resonant structure in tau(-) -->K(-)pi(+)pi(-) nu(tau)
decays. We measure the relative fractions of K-1(1270) and K-1(1400) reson
ances in these decays, as well as the K-1 masses and widths. Our fitted K-1
resonances are somewhat broader than previous hadroproduction measurements
, and in agreement with recent CERN LEP results from tau decay. The larger
central value of our measured width supports models which attribute the sma
ll tau(-) --> K- pi(+) pi(-) nu(tau) branching fraction to larger K-1 width
s than are presently tabulated. We also determine the K-a-K-b mixing angle
theta(K).