Smart to be charged with leaving the scene of an accident rather than negligent homicide, or worse.
My theory is that Trooper Beardsley was at a cop bar with his girlfriend and his fellow troopers and their wives/girlfriends. He will lie that he wasn't drinking or that he only had "two beers" and his fellow cops will lie that they only saw him have two beers or that they don't recall seeing him drink at all. The bartender who knows very well that Trooper Beardsley and the other troopers were blotto that night, will deny Beardsley was drunk or that any cop ever gets drunk during her shift, if only because the cops are her biggest customers and tip her well. In addition, if she admits serving alcohol to drunk cops, the very drunk cops that she served alcohol to might arrest her for serving an intoxicated person in violation of state liquor laws. Lastly, the bar owner will soon discover that the CCTV surveillance camera that should conclusively prove that Beardsley and the other troopers were a sober as a Baptist preacher on Easter morning, was broken that evening even though it worked fine the night before and the night after the incident.
Please note that this is just a theory that may or may not prove true in whole or in part. My theory is based upon solely upon conjecture and my experiences many, many years ago as a bartender at a cop bar in upstate NY, where I learned that cops are mean nasty drunks, who routinely drive with BALs well in excess of what would land anyone else in jail, and they will lie through their teeth to protect their own and to make an arrest stick.