"You also can sue the manufacturer if a train runs a red because the LED broke" FYI, MTA operating procedures require trains to stop when a signal is not light

"You also can sue the manufacturer if a train runs a red because the LED broke" FYI, MTA operating procedures require trains to stop when a signal is not lighted, then coordinate by radio before proceeding. There is also a defense-in-depth strategy: the interlocking maintains 4 red signals between trains, so a collision in theory would require 4 failing signals, 4 failing stop arms (which automatically stop trains that ignore red signals) and a train operator ignoring the rules.