The engineer who fell asleep on the job, just before his train derailed in the Bronx, killing four people, is suing his former employer for $10 million dollars.
More than 70 people were injured in the 2013 crash of a Metro-North train.
Railroads across the U.S. are making uneven progress in implementing Positive Train Control (PTC), the technology designed to automatically stop a train before collisions occur.