A train arrives at Federal Triangle Metro station in D.C. on Dec. 1, 2020. (Matt McClain/The Washington Post)
Three investigations arising from the derailment have been under way for weeks, and so far, what has been made public is cause for worry, not optimism. The inspectors general of both Metro itself and the federal Transportation Department are looking into the derailment, as is the National Transportation Safety Board. And still there is no official word on what caused the recurring wheel issue that led a train with about 200 passengers aboard to slip off the tracks near Arlington Cemetery on Oct. 12, nor how to ensure it never happens again.