To have committed a specific crime, say, murder in the first degree, one must

(1) have behaved in some overt way which the law aims to prevent, i. e. to have killed someone, (2) to be unable to offer an acceptable justification for what one did, and (3) to be unable to offer an acceptable excuse.

To commit a crime (then) is to behave in a certain way and to be unable to offer an acceptable defense. There are twelve major defenses: three major types of justification and nine major types of excuses which either completely exculpate or mitigate conduct which the law aims to prevent. The three major justifications are:

(1) an act, otherwise subject to punishment, is not a crime if done in reasonable self-defense against unlawful attack, by a soldier or police officer in line of duty, in order to prevent treason or a violent felony , or in the service of public welfare (i. e. destruction of property in order to bring a forest fire under control);

(2) an act, otherwise subject to punishment, is not a crime if performed because someone threatened the agent with loss of life or personal injury, in such a way and in circumstances as would intimidate a normal person of ordinary firmness; and

(3) an act, otherwise subject to punishment, is not a crime if, in case one does not, the result will be worse than if one had and that what would have happened, had one not acted, would have happened anyway.

Excuses: Exculpatory and Mitigating

Excuses in law may exculpate or mitigate. A person is usually exculpated if

(4) the person causes harm the law aims to prevent by accident. However, if the agent is committing an unlawful act when the accident occurs, he is often treated as if he intended to cause the accident;

(5) the person commits an act, otherwise subject to punishment, but does so because of an innocent mistake in his belief about the facts. Thus, it is lawful to shoot a person who has broken into one's house for the purpose of theft and if a person shoots her husband on account of a genuine and innocent supposition that it was a burglar, she is exonerated.

(6) If a person is physically compelled to do a deed that the law would otherwise punish, i.e. his hand holding the dagger is guided by the hands of someone much stronger than he is, he is thought not to have acted at all, and will not be prosecuted.

(7) The law excuses a person for doing what it is impossible not to do, i. e. she is stopped in a "No Stopping" Zone because of a traffic jam and the car cannot move.

(8) A person under seven years of age cannot commit a crime; and he is not guilty of a crime if he is under fourteen years of age and malicious intent cannot be shown - although he may be liable for treatment under rules for juveniles.

(9) A person is excused if he performed an act, otherwise prohibited by law, while walking in his sleep. Insanity and its variants also exculpate a person if the person committed the act but "did not know the nature and quality of the act he was performing or, if he did know, did not know that what he was doing was wrong."

(10) A person may also be found not guilty of a crime, otherewise punishable by law, if he acted because of involuntary intoxication. There are also mitigating excuses which reduce the seriousness of the crime and can change the crime from one crime to another, i.e., from murder in the first degree to involuntary manslaughter.

(11) A person, in the case of homicide, may be not guilty of one crime, but guilty of a lesser one, if he acted impulsively. Premeditation is commonly necessary for murder in the first degree. If one kills in the heat of passion, without forethought, one is only guilty of second degree murder. Indeed, if such heat of passion is provoked in some reasonably defensable fashion, i.e., finding one's husband in the act of adultery, the person may be guilty only of manslaughter.

(12) Although voluntary intoxication may not exculpate on the presumption that one had some say in deciding to intoxicate oneself in the first place, it may reduce the degree of the crime.

Prepared: February 4, 2003 - 5:02:29 PM
Edited and Updated, February 5, 2003

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