i was thinking more about the engineer here as well. those five people were on the track for whatever reason. if the engineer were to consciously change course to me he would be a murderer. if he does nothing it's an extremely unfortunate accident.
That's absurd. If he makes a decision to be laissez-faire in this situation, he'd still be killing five men - through his deliberate refusal to act where he had ample time and ability to do so.
It's a shitty situation no matter how you look at it, and if he is a murderer for consciously turning the train on the one man, so is he the same and more for consciously allowing the train to run over the five men where he could have stopped it.
The difference is in how many lives he saves in each situation. In the former, he saves five men for the one. In the latter, he saves one for the five lost. If you were railroaded (in this case, literally) into the black-and-white decision between tacitly allowing many to die or intentionally killing one, most people would say that you'd be in the right for making the deliberate choice of killing one.
Try and consider the people on the receiving end of such a deal, as well. You tell the five men that you just killed one man to save their lives, they can share the burden of that guilt. If they're strong enough, they can cope with that together and likely avert any serious depressive episodes that could lead to a suicide.
But tell the single man that you just killed five people to save his life, and his reaction could be entirely different. Essentially, he has to live with the guilt of five people being murdered on his behalf. The collective guilt of five lives, potentially five devastated families, upon that one man's shoulders, could lead him to take his own life later on down the line - and then you have six dead where you only had five before, or could have only had one in the previous situation.
And if you were in the engineer's position, could you really live with yourself if you allowed five people to die through conscious inaction? I can't imagine how it wouldn't take some serious mental gymnastics to absolve oneself of responsibility in such a case.