Murder (United States law)
In the United States, the principle of dual sovereignty applies to homicide as to other crimes. If murder is committed within the borders of a state, that state has jurisdiction. Similarly, if the crime is committed in the District of Columbia (otherwise known as Washington, D.C.), the D.C Superior Court (the equivalent of a state court in the District) retains jurisdiction, though in some cases involving U.S. government property or personnel, the federal courts may have exclusive jurisdiction.
If the victim is a federal official, an ambassador, consul or other foreign official under the protection of the United States, or if the crime took place on federal property or involved crossing state lines, or in a manner that substantially affects interstate commerce or national security, then the federal government also has jurisdiction. If a crime is not committed within any state, then Federal jurisdiction is exclusive: examples include naval or U.S.-flagged merchant vessels in international waters and U.S. military bases worldwide. In addition, murder by a member of the United States military anywhere in the world is a violation of Article 118 of the Uniform Code of Military Justice and can result in a servicemember suspected of murder being tried by a general court-martial. In cases where a murder involves both state and federal jurisdiction, the offender can be tried and punished separately for each crime without raising issues of double jeopardy, unless the court believes that the new prosecution is merely a "sham" forwarded by the prior prosecutor. In the United States there is no statute of limitations on the crime of murder.
Modern codifications tend to create a genus of offenses, known collectively as homicide, of which murder is the most serious species, followed by manslaughter which is less serious, and ending finally in justifiable homicide, which is not a crime at all. Because there are 53 jurisdictions, each with its own criminal code, this section treats only the crime of murder, and does not deal with state-by-state specifics.
At base, murder consists of an intentional unlawful act with a design to kill and fatal consequences. Generally, an intention to cause great bodily harm is considered indistinguishable from an intention to kill, as is an act so inherently dangerous that any reasonable person would realize the likelihood of fatality. Thus, if the defendant hurled the victim from a bridge, it is no defense to argue that harm was not contemplated, or that the defendant hoped only to break bones.
Under U.S. federal law, murder is the unlawful killing of a human being with malice aforethought. Malice can be expressed (intent to kill) or implied. Implied malice is proven by acts that involve reckless indifference to human life or in a death that occurs during the commission of certain felonies (the felony murder rule). The exact terms of the felony murder vary tremendously from jurisdiction to jurisdiction. Life sentencing for murder in the United States has a mean of 349 months (29 years one month) and a median of 480 months (40 years).
However, some states' sentencings contemplate a full life's confinement, whence the sentence of confinement is not deemed fulfilled while the convicted person lives; and the only way to fulfill the sentence (and thereby obtain release from confinement) is by the individual's death. These sentences are termed natural life and/or life without the possibility of parole. Additionally, life without the possibility of parole can be defined under special circumstances for example in the course of a robbery or additional crimes. (People v. Horn) Court of Appeals of California, Fourth District, Division One
Degrees of murder in the United States 
States have adopted several different schemes for classifying murders by degree. The most common separates murder into two degrees, and treats voluntary and involuntary manslaughter as separate crimes that do not constitute murder.
- First degree murder is any murder that is willful and premeditated. Felony murder is typically first degree.
- Second degree murder is a murder that is not premeditated or planned in advance.
- Voluntary manslaughter (often referred to as third degree murder) sometimes called a "Heat of Passion" murder, is any intentional killing that involved no prior intent to kill, and which was committed under such circumstances that would "cause a reasonable person to become emotionally or mentally disturbed." Both this and second degree murder are committed on the spot, but the two differ in the magnitude of the circumstances surrounding the crime. For example, a bar fight that results in death would ordinarily constitute second degree murder. If that same bar fight stemmed from a discovery of infidelity, however, it may be mitigated to voluntary manslaughter.
- Involuntary manslaughter stems from a lack of intention to cause death but involving an intentional, or negligent, act leading to death. A drunk driving-related death is typically involuntary manslaughter. Note that the "unintentional" element here refers to the lack of intent to bring about the death. All three crimes above feature an intent to kill, whereas involuntary manslaughter is "unintentional," because the killer did not intend for a death to result from their intentional actions. If there is a presence of intention it relates only to the intent to cause a violent act which brings about the death, but not an intention to bring about the death itself. 
The Model Penal Code classifies homicides differently, without degrees. Under it, murder is any killing committed purposefully and knowingly, manslaughter is any killing committed as a result of recklessness, and negligent homicide is any killing resulting from negligence.
Some states classify their murders differently. In Pennsylvania, California, and Massachusetts, first degree murder encompasses premeditated murders, second degree murder encompasses accomplice liability, and third degree serves as a catch-all for other murders. In New York, first-degree murder involves "special circumstances," such as the murder of a police officer or witness to a crime, multiple murders, or murders involving torture. Under this system, second degree murder is any other premeditated murder.
The New York statutes also recognize "murder for hire" as first degree murder.  Texas uses a similar scheme to New York, but refers to first-degree murder as "capital murder," a term which typically applies only to those crimes that merit the death penalty. Some states, such as Florida, do not separate the two kinds of manslaughter.
Punishment for murder 
|Second degree murder||Imprisonment for life or any term|
|Second degree murder by an inmate, even escaped, serving a life sentence||Life imprisonment|
|First degree murder||Death sentence or life sentence|
|Murder under UCMJ Article 118 Clause (2) or (3)||Any legal punishment as directed by the court-martial|
|Murder under UCMJ Article 118 Clause (1) or (4)||Death or life imprisonment|
By states 
Fetal homicide in the United States 
Under the common law, an assault on a pregnant woman resulting in a stillbirth was not considered murder; the child had to have breathed at least once to be a human being. Remedies were limited to criminal penalties for the assault on the mother and tort action for loss of the anticipated economic services of the lost child and/or for emotional pain and suffering. With the widespread adoption of laws against abortion, the assailant could be charged with that offense, but the penalty was often only a fine and a few days in jail.
When the Supreme Court greatly reduced laws prohibiting abortions in Roe v. Wade (1973) those sanctions became harder to use. This meant that an assault which ensured that the baby never breathed would result in a lesser charge. Various states passed "fetal homicide" laws, making killing of an unborn child murder; the laws differ about the stage of development at which the child is protected.
After several well-publicized cases, Congress passed the Unborn Victims of Violence Act, which specifically criminalizes harming a fetus, with the same penalties as for a similar attack upon a person, when the attack would be a federal offense. Most such attacks fall under state laws; for instance, Scott Peterson was convicted of killing his unborn son as well as his wife under California's pre-existing fetal homicide law.
Murder sentencing guidelines in the United States 
In Arizona, a person is charged with murder when the offender knowingly and intentionally causes the death of a person or unborn child. The murder must be premeditated. In the state of Arizona, if one is found guilty of murder 1, there is the possibility of receiving the death penalty.
In Florida, a person is guilty of first degree murder when it is perpetrated from a premeditated design to result in the death of a human being. A person is also guilty of first degree murder if they cause the death of any individual during the commission of a predicate felony regardless of actual intent or premeditation. This is called felony murder. This offense is categorized as capital offense, if convicted the offender could possibly receive the death penalty in the State of Florida.
In Hawaii, a person commits first degree murder when the crime involves one or more specific elements:
- Multiple victims killed
- A law enforcement officer, judge, or prosecutor killed (in connection with their respective duties)
- A witness in a criminal case killed (in connection with the person being a witness)
- Murder committed for hire (with the charge applying to both the murderer and the person who paid the murderer)
- Murder committed by an imprisoned person
Louisiana states that homicide in the first degree is killing of a human being with intent. There are other specific guidelines like killing a police officer or firefighter is an automatic first degree charge or intent to kill more than one person is automatically a first degree charge. In the State of Louisiana you can receive life imprisonment or the death penalty.
In Michigan, a person is found guilty of first degree murder when murder is perpetrated by means of poison, lying in wait, or any other willful, deliberate, and premeditated killing. In Michigan the top penalty the perpetrator can receive is life imprisonment.
In Missouri, "A person commits the crime of murder in the first degree if he knowingly causes the death of another person after deliberation upon the matter." Murder in the second degree occurs when (1) the defendant knowingly causes the death of another person or causes their death "with the purpose of causing serious physical injury" or (2) the perpetration, attempted perpetration, or immediate flight from a felony results in a person being killed.
Murder in the first degree is punishable by imprisonment for life without eligibility for release except by act of the governor, or by death if the defendant is old enough. Murder in the second degree is punishable by ten to thirty years imprisonment or a life sentence.
In Nevada, first degree murder is the unlawful killing of a human being with malice and aforethought, either expressed or implied. If a serial killer is found guilty with aggravating circumstances, for example killing someone with torture or killing a stranger with no apparent motive, then the State can seek the death penalty or a sentence of life without parole.
In the state of Washington, a person is found guilty of first degree murder when there is a premeditated intent to cause the death of another person. Murder in the first degree is a class A felony in the state of Washington. If a person is convicted of first degree murder, they will not receive anything lower than life imprisonment.
The offender can possibly get a charge of aggravated first degree murder if they commit first degree murder and have an aggravating circumstance, for example if they kill a police officer. In this case they can receive the death penalty.
See also 
- See generally, Title 18 U.S. Code
- Koon v. United States, 518 U.S. 81 (1996)
- 18 U.S.C. § 1111
- US Dept. of Justice: Felony Defendants in Large Urban Counties, 2002
- "First Degree Murder Definition - FindLaw". Criminal.findlaw.com. Retrieved 2012-12-18.
- "Second Degree Murder Definition - FindLaw". Criminal.findlaw.com. Retrieved 2012-12-18.
- "Voluntary Manslaughter Definition - FindLaw". Criminal.findlaw.com. Retrieved 2012-12-18.
- "Involuntary Manslaughter Definition - FindLaw". Criminal.findlaw.com. Retrieved 2012-12-18.
- [dead link]
- See, e.g., N.Y.State Penal Law section 125.27, found at N.Y. State Legislative web site (search for Penal Law § 125.27).
- See, e.g., N.Y. State Penal Law section 125.25, found at N.Y. State Legislative web site (search for Penal Law § 125.25).
- Murder Charge in New York. June 2010. Bukh Law Firm, PC - 14 Wall St, New York NY 10005 - (212) 729-1632. New York murder lawyer
- "Title 18 - CRIMES AND CRIMINAL PROCEDURE :: 2010 US Code :: US Codes and Statutes :: US Law :: Justia". Law.justia.com. 2011-01-07. Retrieved 2012-12-18.
- "10 USC § 918 - Art. 118. Murder | LII / Legal Information Institute". Law.cornell.edu. Retrieved 2012-12-18.
- "13-1105 - First degree murder; classification". Azleg.state.az.us. Retrieved 2010-06-25.
- "Statutes & Constitution :View Statutes". flsenate.gov. Retrieved 2010-06-25.
- "Hawaii Revised Statutes §707-701". Hawaii State Legislature. 2010. Retrieved 2011-09-06.
- "Hawaii Revised Statutes §706-656". Hawaii State Legislature. 2010. Retrieved 2011-09-06.
- "Michigan Legislature - Section 750.316". Legislature.mi.gov. Retrieved 2010-06-25.
- "Section 565-020 First degree murder, penalty-person un". Moga.mo.gov. 2012-08-28. Retrieved 2012-12-18.
- "Section 565-021 Second degree murder, penalty". Moga.mo.gov. 2012-08-28. Retrieved 2012-12-18.
- "Section 558-011 Sentence of imprisonment, terms-condit". Moga.mo.gov. 2012-08-28. Retrieved 2012-12-18.
- "NRS: CHAPTER 200 - CRIMES AGAINST THE PERSON". Leg.state.nv.us. Retrieved 2010-06-25.
- "RCW 9A.32.030: Murder in the first degree". Apps.leg.wa.gov. Retrieved 2010-06-25.
- "RCW 9A.32.040: Murder in the first degree — Sentence". Apps.leg.wa.gov. Retrieved 2010-06-25.
- "RCW 10.95.020: Definition". Apps.leg.wa.gov. Retrieved 2010-06-25.