"Spectropolarimetry is a promising method to probe asymmetry in the supernova ejecta and its surrounding environment. Previous optical spectropolarimetric studies of core-collapse SNe reveal that the continuum polarization of type II-P SNe is typically low during the plateau phase, then rises as the SN enters the nebular phase. This rising polarization is generally interpreted as an evidence for the asymmetric inner region being revealed as the SN photosphere recedes. This is perhaps the only direct observational evidence for asymmetric explosion mechanism invoked in virtually all core-collpase models. However, a recent theoretical work show that light echo from CSM dust can also produce a similar polarization evolution since the highly polarized echos of the SN peak emission typically emerge as the unpolarized SN light fades. This effect usually has not been accounted for in spectropolarimetric analyses in the literature. Near-infrared observations can help break this degeneracy since the light echo effect is expected to be an order of magnitude lower in the near-IR due to the diminishing dust scattering opacity at longer wavelengths. The polarization from electron scattering in the ejecta (or in the ionized CSM of interacting events), however, remain the same. We discuss ways to use concurrent optical and near-IR spectropolarimetric observations to constrain geometry of both the SN ejecta and the dusty CSM. To demonstrate the feasibility of this new approach, we present the first near-IR spectropolarimetric detection of a nearby type II-P SN 2017eaw using a newly commissioned instrument WIRC+Pol on the 200-inch telescope at Palomar Observatory.   
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