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WIRC+Pol is a newly commissioned low-resolution (R~100), near-infrared (J andH band) spectropolarimetry mode of the Wide-field InfraRed Camera (WIRC) on the200-inch Hale Telescope at Palomar Observatory. The instrument utilizes a novelpolarimeter design based on a quarter-wave plate and a polarization grating(PG), which provides full linear polarization measurements (Stokes I, Q, and U)in one exposure. The PG also has high transmission across the J and H bands.The instrument is situated at the prime focus of an equatorially mountedtelescope. As a result, the system only has one reflection in the light path,providing minimal telescope induced polarization. A data reduction pipeline hasbeen developed for WIRC+Pol to produce linear polarization measurements fromobservations. WIRC+Pol has been on-sky since February 2017. Results from thefirst year commissioning data show that the instrument has a high dispersionefficiency as expected from the polarization grating. We demonstrate thepolarimetric stability of the instrument with RMS variation at 0.2% level over30 minutes for a bright standard star (J = 8.7). While the spectral extractionis photon noise limited, polarization calibration between sources remainlimited by systematics, likely related to gravity dependent pointing effects.We discuss instrumental systematics we have uncovered in the data, theirpotential causes, along with calibrations that are necessary to eliminate them.We describe a modulator upgrade that will eliminate the slowly varyingsystematics and provide polarimetric accuracy better than 0.1%.

WIRC+Pol: a low-resolution near-infrared spectropolarimeter