In short murder is the unlawful killing of another human being with the intention to kill or cause grievous bodily harm. The legal definition used to
describe the act of murder is violence 'with malice aforethought'.
To be a bit more technical:
murder n. the killing of a human being by a sane person, with intent, malice aforethought (prior intention to kill the particular victim or anyone
who gets in the way), and with no legal excuse or authority. In those clear circumstances, this is first-degree murder. By statute many states make
killings in which there is torture, movement of the person (kidnapping) before the killing, as an incident to another crime (as during a hold-up or
rape), and the death of a police officer or prison guard all first degree murders with or without premeditation, and with malice presumed.
Second-degree murder is such a killing without premeditation, as in the heat of passion or in a sudden quarrel or fight. Malice in second degree
murder may be implied from a death due to the reckless lack of concern for the life others (such as firing a gun into a crowd, or bashing someone with
any deadly weapon). Depending on the circumstances and state laws, murder in the first or second degree may be chargeable to a person who did not
actually kill, but was involved in a crime with a partner who actually did the killing or someone died as the result of the crime. (Example: In a
liquor store stick-up in which the clerk shoots back at the hold-up man and kills a bystander, the armed robber can be convicted of at least second
degree murder. To be murder the victim must die within a year of the attack. Death of an unborn child who is "quick" (fetus is moving) can be
murder, provided there was premeditation, malice, and no legal authority. Thus, abortion is not murder under the law. (Example: Jack Violent shoots
his pregnant girlfriend, killing the fetus). Manslaughter, both voluntary and involuntary, lacks the element of malice aforethought.
So, looking at it from a legal point, you cannot be charged with murder seeing that it's not a "human being" - i.e. homo sapien. If by some clever
means somebody convinces the court that Bigfoot actually classifies as a human being, you can always get off by means of "legal excuse". 1. You did
not know that it was human. 2. You can plead self-defence.
You can bet your mother that you will be dragged to court by some animal-rights group for killing an endangered species, animal cruelty, or something
clever. I cannot speak for any judge or jury, but I doubt if you will be found guilty of anything.
History taught us that no picture or video image will ever be good enough to act as "proof, thus we'll have to have something tangible to show. A
live Bigfoot would be ideal.
@mj13
It would be amazing if Bigfoot were to be Paranthropus boisei. It will most definitely shake the scientific community and open so many doors.