Gilbert Drogheo, 32, was shot and killed during a confrontation at Borough Hall station on the evening commute of March 10, 2015. Drogheo, an electrician’s apprentice and father, was involved in a verbal dispute with 69-year-old retired correction officer William Groomes that witnesses describe differently — some saying Drogheo and a friend, Joscelyn Evering, were harassing other passengers, others saying Groomes started the conflict. The argument turned physical and moved from the train onto the mezzanine, where Groomes, who held a concealed carry license, drew a firearm and shot Drogheo once in the chest.

Drogheo was taken to a hospital and pronounced dead; the medical examiner ruled the death a homicide. Groomes was taken into custody after the shooting but released without charges; Evering, 28 at the time, was arrested and charged with assault and menacing. The Brooklyn District Attorney concluded its review of witness interviews and video evidence and said there was not enough to prove a criminal act beyond a reasonable doubt, a decision that angered Drogheo’s family, who intended to pursue a civil suit.

Does anyone have additional details about the confrontation on the train or the mezzanine that could clarify what started the fight?