  We measure the temperature and frequency dependence of the complex Hall angle
for normal state YBa$_2$Cu$_3$O$_7$ films from dc to far-infrared frequencies
(20-250 cm$^{-1}$) using a new modulated polarization technique. We determine
that the functional dependence of the Hall angle on scattering does not fit the
expected Lorentzian response. We find spectral evidence supporting models of
the Hall effect where the scattering $\Gamma_H$ is linear in T, suggesting that
a single relaxation rate, linear in temperature, governs transport in the
cuprates.

Superconductivity