Proportionality is a principle in law which covers two distinct (although related) concepts. Within municipal (domestic) law

Municipal law

Municipal law is the national, domestic, or internal law of a sovereign state defined in opposition to international law. Municipal law includes not only law at the national level, but law at the state, provincial, territorial, regional or local levels...

 it is used to convey the idea that the punishment of an offender should fit the crime. Under international humanitarian law

International humanitarian law

International humanitarian law , often referred to as the laws of war, the laws and customs of war or the law of armed conflict, is the legal corpus that comprises "the Geneva Conventions and the Hague Conventions, as well as subsequent treaties, case law, and customary international law." It...

 governing the legal use of force

Laws of war

The law of war is a body of law concerning acceptable justifications to engage in war and the limits to acceptable wartime conduct...

 in an armed conflict, proportionality and distinction

Distinction (law)

Distinction is a principle under international humanitarian law governing the legal use of force in an armed conflict, whereby belligerents must distinguish between combatants and civilians...

are important factors in assessing military necessity

Military necessity

Military necessity, along with distinction, and proportionality, are three important principles of international humanitarian law governing the legal use of force in an armed conflict.-Attacks:...

.

Criminal law

Within law, the principle of proportional justice is used to describe the idea that the punishment of a certain crime should be in proportion to the severity of the crime itself. In practice, systems of law differ greatly on the application of this principle. In some systems, this was interpreted as lex talionis, (an eye for an eye). In others, it has led to a more restrictive manner of sentencing. For example, all European Union countries have accepted as a treaty obligation that no crime warrants the death penalty, whereas some other countries in the world do use it.

International law

The incidental (i.e., unintended) harm caused to civilians or civilian property must be proportionate and not excessive in relation to the concrete and direct military advantage anticipated by an attack on a military objective.

Luis Moreno-Ocampo was the Chief Prosecutor at the International Criminal Court

International Criminal Court

The International Criminal Court is a permanent tribunal to prosecute individuals for genocide, crimes against humanity, war crimes, and the crime of aggression .It came into being on 1 July 2002—the date its founding treaty, the Rome Statute of the...

 who investigated allegations of War Crime

War crime

War crimes are serious violations of the laws applicable in armed conflict giving rise to individual criminal responsibility...

s during the 2003 invasion of Iraq. He published an open letter containing his findings; in a section titled "Allegations concerning War Crimes", he elucidates this use of proportionality:

See also

• Ryuichi Shimoda et al. v. The State
  Ryuichi Shimoda et al. v. The State
  Ryuichi Shimoda et al. v. The State was a case brought before the District Court of Tokyo by a group of five survivors of the atomic attacks on Hiroshima and Nagasaki, who claimed the action was illegal under the laws of war and demanded reparations from the Japanese government on the ground that...
  
  
• Let the punishment fit the crime
• Civilian casualty ratio
  Civilian casualty ratio
  In armed conflicts, the civilian casualty ratio is the ratio of civilian casualties to combatant casualties, or total casualties...
  
  

External links

• Eric Engle, The History of the General Principle of Proportionality

• Françoise Hampson military necessity