Homicide is the act of one human killing another. A homicide requires only a volitional act by another person that results in death, and thus a homicide may result from accidental, reckless, or negligent acts even if there is no intent to cause harm. Homicides can be divided into many overlapping legal categories, including murder, manslaughter, justifiable homicide, killing in war (either following the laws of war or as a war crime), euthanasia, and capital punishment, depending on the circumstances of the death. These different types of homicides are often treated very differently in human societies; some are considered crimes, while others are permitted or even ordered by the legal system.
Criminal homicide takes many forms including accidental killing or purposeful murder. Criminal homicide is divided into two broad categories, murder and manslaughter, based upon the state of mind and intent of the person who commits the homicide.
Murder is the most serious crime that can be charged following a homicide. In many jurisdictions, homicide may be punished by life in prison or even capital punishment. Although categories of murder can vary by jurisdiction, murder charges fall under two broad categories:
In some jurisdictions, a homicide that occurs during the commission of a dangerous crime may constitute murder, regardless of the actor's intent to commit homicide. In the United States, this is known as the felony murder rule. In simple terms, under the felony murder rule a person who commits a felony may be guilty of murder if someone dies as a result of the commission of the crime, including the victim of the felony, a bystander or a co-felon, regardless their intent--or lack thereof--to kill, and even when the death results from the actions of a co-defendant or third party who is reacting to the crime.
Manslaughter is a form of homicide in which the person who commits the homicide either does not intend to kill the victim, or kills the victim as the result of circumstances that would cause a reasonable person to become emotionally or mentally disturbed to the point of potentially losing control of their actions. The penalty for manslaughter is normally less than the penalty for murder. The two broad categories of manslaughter are:
Another form of manslaughter in some jurisdictions is constructive manslaughter, which may be charged in the event that a person causes a death without intention, but as the result of violating an important safety law or regulation.
Not all homicides are crimes, or subject to criminal prosecution. Some are legally privileged, meaning that they are not criminal acts at all. Others may occur under circumstances that provide the defendant with a full or partial defense to criminal prosecution. Common defenses include:
if the defendant in a capital case is sufficiently mentally disabled in the United States they cannot be executed. Instead, the individual is placed under the category of "insane".
The availability of defenses to a criminal charge following a homicide may affect the homicide rate. For example, it has been suggested that the availability of "stand your ground" defense has resulted in an increase in the homicide rate in U.S. jurisdictions that recognize the defense, including Florida.
Killing by governments and the agents thereof may be considered lawful or unlawful according to:
Types of state killings include:
Scholars study especially large homocide events (typically 50,000 deaths in five years or less) as mass killings. Some medium- and large-scale mass killings by state actors have been term massacres, though not all such killings have been so named. The term "democide" has been coined by Rudolph Rummel to describe "murder by government" in general, which includes both extrajudicial killings and widespread systematic homocide.
Killing by government might be called "murder" or "mass murder" in general usage, especially if seen by the commentator as unethical, but the domestic legal definitions of murder, manslaughter, etc., usually exclude killings carried out by lawful government action.
Deliberate massacres of captives or civilians during wartime or periods of civil unrest by the state's military forces, include those committed by Genghis Khan, the Golden Horde, the troops of Vlad the Impaler, the Empire of Japan, the Soviet Union, and Nazi Germany during the Second Sino-Japanese War and World War II, the Nanjing Massacre, the Katyn Forest Massacre of Polish citizens in 1940 and the massacres of political prisoners after the launch of Operation Barbarossa, the Three Alls Policy, the massacre of Soviet Jews at Babi Yar, the mass murder of the Hungarian, Serbian and German population in Vojvodina in the "Vengeance of Bacska", the murder of 24 unarmed villagers by British troops in the Batang Kali massacre during the Malayan Emergency, the mass killings in Indonesia during Suharto's rise to power, the murder of suspected leftists during Operation Condor in South America, the murder of Vietnamese civilians by American soldiers in the My Lai Massacre during the Vietnam War, the genocidal massacres of the Maya population during the Guatemalan Civil War, the massacre at El Mozote during the Salvadoran Civil War, and repeated attacks on civilians during the Syrian Civil War including the Al-Qubeir massacre.
Actions in which the state indirectly caused the death of large numbers of people include man-made disasters caused by the state, such as the Holodomor famine in the Soviet Union, the Khmer Rouge years in Cambodia, and the famines and poverty caused by the Great Leap Forward and the Cultural Revolution in the People's Republic of China.
A 2011 study by the United Nations Office on Drugs and Crime brought together a wide variety of data sources to create a worldwide picture of trends and developments. Sources included multiple agencies and field offices of the United Nations, the World Health Organization, and national and international sources from 207 countries.
The report estimated that in 2010, the total number of homicides globally was 468,000. More than a third (36%) occurred in Africa, 31 percent in the Americas, 27 percent in Asia, five percent in Europe and one percent in Oceania. Since 1995, the homicide rate has been falling in Europe, North America, and Asia, but has risen to a near "crisis point" in Central America and the Caribbean. Of all homicides worldwide, 82 percent of the victims were men, and 18 percent were women. On a per-capita scaled level, "the homicide rate in Africa and the Americas (at 17 and 16 per 100,000 population, respectively) is more than double the global average (6.9 per 100,000), whereas in Asia, Europe and Oceania (between 3 and 4 per 100,000) it is roughly half".
UNODC, in its 2013 global report, estimated the total number of homicides worldwide dropped to 437,000 in 2012. Americas accounted for 36 percent of all homicides globally, Africa 21 percent, Asia 38 percent, Europe five percent and Oceania 0.3%. The world's average homicide rate stood at 6.2 per 100,000 population in 2012, but Southern Africa region and Central America have intentional homicide rates four times higher than the world average. They are the most violent regions globally, outside of regions experiencing wars and religious or sociopolitical terrorism. Asia exclusive of West Asia and Central Asia, Western Europe, Northern Europe, as well as Oceania had the lowest homicide rates in the world. About 41 percent of the homicides worldwide occurred in 2012 with the use of guns, 24 percent with sharp objects such as knife, and 35 percent by other means such as poison. The global conviction rate for the crime of intentional homicide in 2012 was 43 percent.
[W]here homicide rates are high and firearms and organized crime in the form of drug trafficking play a substantial role, 1 in 50 men aged 20 will be murdered before they reach the age of 31. At the other, the probability of such an occurrence is up to 400 times lower.
[H]omicide is much more common in countries with low levels of human development, high levels of income inequality and weak rule of law than in more equitable societies, where socioeconomic stability seems to be something of an antidote to homicide.
Women murdered by their past or present male partner make up the vast majority of [homicide] victims worldwide....