Red Line dragging death likely caused by short circuit in door, NTSB finds

A short circuit on an MBTA Red Line train allowed it to accelerate out of a station while a passenger was trapped in a door, despite the presence of a failsafe that typically prevents vehicle movement while a door is obstructed, federal investigators concluded.

The National Transportation Safety Board deemed the short circuit the probable cause of the fatal accident that killed Robinson Lalin on April 10, 2022.

"Under normal operating conditions, the passenger door interlock circuit would have prevented train propulsion if a door obstruction was detected or the doors were open," the agency wrote in a report published Tuesday. "However, the short circuit that bypassed the passenger door interlock circuit allowed the train to proceed even with the passenger's upper body obstructing the accident railcar doors."

Investigators said the operator of the Red Line train left the station without confirming all pilot lights were off, which confirms that passenger doors have closed. That violated the MBTA's departure policy, according to the NTSB.

They also found a 19-foot "blind spot" in a camera view of the station platform, which blocked sight of the door in which Lalin became trapped.

An NBC10 Boston investigation found there were hundreds of door problems reported on MBTA trains over the years before the deadly accident.

Nearly a year ago, a man was killed after his arm got caught in the door of a Red Line train. NBC10 Investigator Cory Smith looked into how often trouble on the T involves train doors.