What is Murder?

Legal Definition
Murder is the unlawful killing of another human without justification or valid excuse, especially the unlawful killing of another human being with malice aforethought. This state of mind may, depending upon the jurisdiction, distinguish murder from other forms of unlawful homicide, such as manslaughter. Manslaughter is a killing committed in the absence of malice, brought about by reasonable provocation, or diminished capacity. Involuntary manslaughter, where it is recognized, is a killing that lacks all but the most attenuated guilty intent (mens rea), recklessness.

Most societies consider murder to be a very serious crime, and thus believe that the person charged should receive harsh punishments for the purposes of retribution, deterrence, rehabilitation, or incapacitation. In most countries, a person convicted of murder generally faces a long-term prison sentence, possibly a life sentence where permitted.

In many common law jurisdictions, a person convicted of murder will receive a mandatory life sentence. In jurisdictions where capital punishment exists, the death penalty may be imposed for such an act; however, this practice is now less common.
-- Wikipedia
Legal Definition
Murder occurs when one human being unlawfully kills another human being. See Homicide. The precise legal definition of murder varies by jurisdiction. Most states distinguish between different degrees of murder. Some other states base their murder laws on the Model Penal Code.
Background: Common Law Murder
At common law, murder was defined as killing another human being with malice aforethought. Malice aforethought is a legal term of art, that encompasses the following types of murder:
  • "Intent-to-kill murder"
  • "Grievous-bodily-harm murder" - Killing someone in an attack intended to cause them grievous bodiliy harm. For example, if a person fatally stabbed someone, even if she only intended to wound her victim, she could still be executed.
  • "Felony-murder" - Killing someone while in the process of committing a felony. Note that at common law, there were few felonies, and all carried the death penalty. For example, at common law, robbery was a felony. So if a robber accidentally killed someone during a robbery, the robber could be executed.
  • "Depraved heart murder" - Killing someone in a way that demonstrates a callous disregard for the value of human life. For example, if a person intentionally fires a gun into a crowded room, and someone dies, the person could be convicted of depraved heart murder.
These definitions are valuable because they inform subsequent reforms of American murder law.
The Pennsylvania Method
The Pennsylvania Method is a catch-all term for systems of classifying murder by degree. Certain, specified types of murder were first-degree murder, and carried the death penalty. All other types of murder were second-degree murder, which did not carry the death penalty.

First-Degree Murder includes:
  • Willful, deliberate, and premeditated murder.
  • Particularly heinous types of murder. For example, in the original Pennsylvania statute, this included poisoning and lying in wait to kill someone by ambush.
  • Felony-murder, but only for certain listed felonies. For example, in the original Pennsylvania statute, the only eligible felonies were arson, rape, robbery, and burglary.
At present, most states either use the Pennsylvania Method or a similar method to categorize murder.
The Model Penal Code
The Model Penal Code moved away from the traditional common law approach to murder. Under the Model Penal Code, the following constitute murder:
  • Purposefully or knowingly killing another human being. This functions much the same as the common law rule against intentional murder.
  • Killing another human being in circumstances showing extreme recklessness. This functions much the same as the common law's depraved heart murder rule.
  • Felony-murder. The Model Penal Code disfavors but does not eliminate applying the death penalty for killings that occur during the commission of a felony. Instead of framing the rule as a felony-murder rule, it creates a rebuttable presumption that killings that occur during the commisison of listed dangerous felonies show extreme recklessness for purposes of the code's other murder provisions.

Related Topics
Legal Definition
Crim. law. This, one of the most important crimes that can be committed against individuals, has been variously defined. Hawkins defines it to be the wilful killing of any subject whatever, with malice aforethought, whether the person slain shall be an Englishman or a foreigner. B. 1, c. 13, s. 3. Russell says, murder is the killing of any person under the king's peace, with malice prepense or aforethought, either express or implied by law. 1 Rus. Cr. 421. And Sir Edward Coke, 3 Inst. 47, defines or rather describes this offence to be, " when a person of sound mind and discretion, unlawfully killeth any reasonable creature in being, and under the king's peace, with malice aforethought either express or implied."

2. This defnition, which has been adopted by Blackstone, 4 Com. 195; Chitty, 2 Cr. Law, 724; and others, has been severely and perhaps justly criticised. What, it has been asked, are sound memory and understanding? What has soundness of memory to do with the act; be it ever so imperfect, how does it affect the guilt? If discretion is necessary, can the crime ever be committed, for, is it not the highest indiscretion in a man to take the life of another, and thereby expose his own? If the person killed be an idiot or a new born infant, is he a reasonable creature? Who is in the king's peace? What is malice aforethought? Can there be any malice afterthought? Livingst. Syst. of Pen. Law; 186.

3. According to Coke's definition there must be, lst. Sound mind and memory in the agent. By this is understood there must be a will, (q. v.) and legal discretion. (q. v.) 2. An actual killing, but it is not necessary that it should be caused by direct violence; it is sufficient if the acts done apparently endanger. life, and eventually fatal. Hawk. b. 1, c. 31, s. 4; 1 Hale, P. C. 431; 1 Ashm. R. 289; 9 Car. & Payne, 356; S. C. 38 E. C. L. R. 152; 2 Palm. 545. 3. The party killed must have been a reasonable being, alive and in the king's peace. To constitute a birth, so as to make the killing of a child murder, the whole body must be detached from that of the mother; but if it has come wholly forth, but is still connected by the umbilical chord, such killing will be murder. 2 Bouv. Inst. n. 1722, note. Foeticide (q. v.) would not be such a killing; he must have been in rerum natura. 4. Malice, either express or implied. It is this circumstance which distiuguishes murder from every description of homicide. Vide art. Malice.

4. In some of the states, by legislative enactments, murder has been divided into degrees. In Pennsylvania, the act of April 22, 1794, 3 Smith's Laws, 186, makes "all murder which shall be perpetrated by means of poison, or by lying in wait, or by any other kind of wilful, deliberate, and premeditated killing, or which shall be committed in the perpetration or attempt to perpetrate, any arson, rape, robbery, or burglary, shall be deemed murder of the first degree; and all other kinds of murder shall be deemed murder of the second degree; and the jury before whom any person indicted for murder shall be tried, shall, if they find the person guilty thereof, ascertain in their verdict, whether it be murder of the first or second degree; but if such person shall be convicted by confession, the court shall proceed by examination of witnesses, to determine the degree of the crime, and give sentence accordingly. Many decisions have been made under this act to which the reader is referred: see Whart. Dig. Criminal Law, h. t.

5. The legislature of Tennessee has adopted the same distinction in the very words of the act of Pennsylvania just cited. Act of 1829, 1 Term. Laws, Dig. 244. Vide 3 Yerg. R. 283; 5 Yerg. R. 340.

6. Virginia has adopted the same distinction. 6 Rand. R. 721. Vide, generally, Bac. Ab. h. t.; 15 Vin. Ab. 500; Com. Dig. Justices, M 1, 2; Dane's Ab. Index, h. t.; Hawk. Index, h. t.; 1 Russ. Cr. b. 3, c. 1; Rosc. Cr. Ev. h. t. Hale, P. C. Index, h. t.; 4 Bl. Com. 195; 2 Swift's Syst. Index, h. t.; 2 Swift's Dig. Index, h. t.; American Digests, h. t.; Wheeler's C. C. Index, h. t.; Stark. Ev. Index, h. t.; Chit. Cr. Law, Index, h. t.; New York Rev. Stat. part 4, c. 1, t. 1 and 2.
-- Bouviers Law Dictionary
Legal Definition
Pleadings. In an indictment for murder, it must be charged that the prisoner "did kill and murder" the deceased, and unless the word murder be introduced into the charge, the indictment will be taken to charge manslaughter only. Foster, 424; Yelv. 205; 1 Chit. Cr. Law, *243, and the authorities and cases there cited.
-- Bouviers Law Dictionary
Legal Definition
The crime committed where a person of sound mind and discretion (that is, of sufficient age to form and execute a criminal design and not legally "insane") kills any human creature in being (excluding quick but unborn children) and in the peaco of the state or nation (including all persons except the military forces of the public enemy in time of war or battle) without any warrant, justification or excuse in law, with malice aforethought, express or implied, that ls, with a deliberate purpose or a design or determination distinctly formed in the .mind before the commission of the act, provided that death results from the injury inflicted within one year and a day after its infliction. See Kilpatrick v. Com., 31 Pa. 198; Hotema v. U. S., 186 U. S. 413, 22 Sup. Ch 895, 46 L. Ed. 1225; Guiteau's Case (D. Ct) 10 Fed. 161; Clarke v. State, 117 Ala. 1, 23 South. 671, 67 Am. St. Rep. 157; People v. Enoch, 13 Wend. (N. Y.) 167, 27 Am. Dec. 197; Kent v. People, 8 Colo. 563, 9 Pac. 852; Com. v. Webster, 5 Cush. (Mass.) 295, 52 Am. Dec. 711; Armstrong v. State, 30 Fla. 170, 11 South. 618, 17 L. R. A. 484 ; U. S. v. Lewis (C. C.) Ill Fed. 632; Nye v. People, 35 Mich. 16. For the distinction between murder and manslaughter and other forms of homicide, see Homicide; Manslaughter. Common-law definitions. The willful killing of any subject whatever, with malice aforethought, whether the person slain shall be an Englishman or a foreigner. Hawk. P. C. b. 1, c. 13, § 3. The killing of any person under the king's peace, with malice prepense or aforethought, either express, or implied by law. 1 Russ. Crimes, 421; Co.m. v. Webster, 5 Cush. (Mass.) 304, 52 Am. Dec. 711. When a person of sound mind and discretion unlawfully killeth any reasonable creature in being, and under the king's peace, with malice aforethought, either express or implied. 3 Inst. 47. Statutory definitions. Murder is the unlawful killing of a human being with malice aforethought Pen. Code Cal. § 187. Whoever kills any human being with malice aforethought, either express or implied, is guilty of murder. Rev. Code Iowa 1880, § 3848 Murder is the unlawful killing of a human being, in the peace of the state, by a person of sound memory and discretion, with malice aforethought, either express or implied. Code Ga. 1882, § 4820. The killing of a human being, without the authority of law, by any means, or in any manner, shall be murder in the following cases: When done with deliberate design to effect the death of the person killed, or of any human being; when done in the commission of an act eminently dangerous to others, and evincing a depraved heart, regardless of human life, although without any premeditated design to effect the death of any particular individual; when done without any design to effect death, by any person engaged in the commission of the crime of rape, burglary, arson, or robbery, or in any attempt to commit such felonies. Rev. Code Miss. 1880, § 2875. Every homicide, perpetrated by poison, lying in wait, or any other kind of willful, deliberate, malicious, and premeditated killing; or committed in the perpetration of, or the attempt to perpetrate, any arson, rape, robbery, or burglary ; or perpetrated from a premeditated design unlawfully and maliciously to effect the death of any human being other than him who is killed; or perpetrated by any act greatly dangerous to the lives of others, and evidencing a depraved mind, regardless of human life, although without any preconceived purpose to deprive any particular person of life,—is murder in the first degree ; and every other homicide committed nnder such circumstances as would have constituted murder at common law is mnrder in the second degree. Code Ain. 1886, § 3725. Degrees of murder. These were unknown at common law, but have been introduced in many states by statutes, the terms of which are too variant to be here discussed in detail. In general, however, it may he said that most states only divide the crime into "murder in the first degree" and "murder in the second degree," though in a few there are as many as five degrees ; and that the general purport of these statutes is to confine murder in the first degree to homicide committed by poison, lying in wait, and other killings committed in pursuance of a deliberate and premeditated design, and to those which accompany the commission of some of the more atrocious felonies, such as burglary, arson, and rape; while murder in the second degree occurs where there is no such deliberately formed design to take life or to perpetrate one of the enumerated felonies as is required for the first degree, but where, nevertheless, there was a purpose to kill (or at least a purpose to inflict the particular injury without caring whether it caused death or not) formed instantaneously in the mind, and where the killing was without justification or excuse, and without any such provocation as would reduce the crime to the rade of manslaughter. In a few states, there is a crime of "murder in the third degree," which is defined as the killing of a human being without any design to effect death by a person who is engaged in the commission of a felony. The fourth and fifth degrees (in New Mexico) correspond to certain classifications of manslaughter elsewhere.
-- Black's Law Dictionary
Legal Definition
The killing of a reasonable being with malice aforethought; express or implied. See 134 Am. St. Rep. 727, note.
-- Ballentine's Law Dictionary