The simple answer is there is no right and wrong answers. Ultimately some possibilities are more right or wrong than others and you have to make the best judgement you possibly can.

And even if you do do what seems best or worse, the small rippling effects could end up saving/killing several other people. At least if the Butterfly Effect theory is to be believed. I believe it's true enough...

Quote Originally Posted by wikipedia
The butterfly effect is a phrase which encapsulates the more technical notion of sensitive dependence on initial conditions in chaos theory. Small variations of the initial condition of a nonlinear dynamical system may produce large variations in the long term behavior of the system. So this is sometimes presented as esoteric behavior, but can be exhibited by very simple systems: for example, a ball placed at the crest of a hill might roll into any of several valleys depending on slight differences in initial position.

The phrase refers to the idea that a butterfly's wings might create tiny changes in the atmosphere that ultimately cause a tornado to appear (or prevent a tornado from appearing). The flapping wing represents a small change in the initial condition of the system, which causes a chain of events leading to large-scale phenomena. Had the butterfly not flapped its wings, the trajectory of the system might have been vastly different.

Recurrence, the approximate return of a system towards its initial conditions, together with sensitive dependence on initial conditions are the two main ingredients for chaotic motion. They have the practical consequence of making complex systems, such as the weather, difficult to predict past a certain time range (approximately a week in the case of weather).

- http://en.wikipedia.org/wiki/Butterfly_effect
Just do what you feel is the best thing to do in a given situation. I doubt that many if any people can accurately predict ALL consequences both positive and negative of their actions. You win some, you lose some.