Lying
I find absolute disregard for due diligence, absolute irrational faith in groundless propositions and willful disregard of sound evaluation of intelligence to be every bit as nefarious as intentionally lying in office.
I don't care if a public train operator had a 'bad day' or 'believed the train would stay on track with all of his heart'- if he is incompetent on the job, then he is responsible for the deaths he causes.
But error, or even incompetence (if this is proven to be the case), isn't deliberate lying, is it? And saying it's just as bad as lying doesn't make it lying either. So stop using the word. You're the one who gets all bent out of shape on exact semantics and meanings.
The engineer in your example wasn't lying either.