Is it Murder or just a Tragedy?

A drowning person is a danger to another who attempts a rescue.

The act of saving a drowning person is immensely complicated by the panicked struggles of the victim to stay afloat and breathing.

Imagine I am lost at sea with at least one person who can’t swim. If I can swim, but am not a trained lifesaver, to preserve my own life I must push away from the non-swimmer. The non-swimmer will likely drown.

Does that make me a murderer?

I did not render aid to a dying person. I can’t be sure the non-swimmer would have dragged us both to the bottom. It’s only the probability, not a certainty. How much, and at what risk, do I owe my fellow human?

Imagine the non-swimmer has me in his grip. To get free and save myself, I may have to strike at him. Now I have taken an active role in causing his death.

Now am I a murderer?

It has been well argued that a person who steals for bread or medicine may be justified. Theft for survival is more morally acceptable than ordinary theft. If I defend my essential bread against a similarly starving person—perhaps to the death—am I a murderer?

The definition of murder is tied to law:

1 : the crime of unlawfully killing a person especially with malice aforethought

But what if the keeper of the law is immoral. Or, just set aside the question of law. Are the deaths in my scenarios morally equivalent to murder?