  We study hadronic polarization and the related anisotropy of the dilepton
angular distribution for the reaction $\pi N \to Ne^+e^-$. We employ consistent
effective interactions for baryon resonances up to spin-5/2 to compute their
contribution to the anisotropy coefficient. We show that the spin and parity of
the intermediate baryon resonance is reflected in the angular dependence of the
anisotropy coefficient. We present results for the anisotropy coefficient
including the $N(1520)$ and $N(1440)$ resonances, which are essential at the
collision energy of the recent data obtained by the HADES collaboration on this
reaction. We conclude that the anisotropy coefficient provides useful
constraints for unraveling the resonance contributions to this process.
