Officer Rafael Casiano was off-duty and driving his personal vehicle on the Bronx River Parkway on Friday, when his car skidded on a rain-slicked road, hit a divider, and flipped over. Investigators at the scene determined that Casiano had been drinking. He was charged with drunken driving and vehicular assault. Casiano hurt his back in the crash; his partner suffered much more serious injuries and is now in a medically-induced coma.