William Rockefeller, the engineer who dozed off before a Metro-North train derailed in the Bronx earlier this month, is unlikely to face criminal charges stemming from the incident that killed four people and left 67 others injured.

DNAinfo reports that investigators have yet to find any evidence suggesting Rockefeller committed a crime. Rockefeller allegedly had a good night of sleep prior to the accident and was alert when he took command of the vehicle. Furthermore, it was determined that Rockefeller's cell phone was off and he was not under the influence of alcohol when the train took the 30 mile per hour curve at 82 miles per hour.

"Falling asleep, by itself, is fundamentally not a crime, not even for a motorman driving a train," a law enforcement source told DNAinfo. "There was nothing mitigating here. He was not drunk, on the phone, or out partying the night before, and he went to sleep at a reasonable hour."

A source reportedly told DNAinfo that prosecutors in the Bronx's District Attorney's Office are carefully reviewing all evidence, but aren't convinced they can get a jury to believe the derailment was the result of anything criminal.

[via DNAinfo]