Prohibition and restriction of weapons

International humanitarian law restricts or prohibits the development, possession and use of certain weapons.

Basic rules

International humanitarian law restricts or prohibits the development, possession and use of certain weapons. The prohibition of such weapons is based on the following criteria: 

  • Weapons that render death inevitable. 
  • Weapons that cause superfluous injury or unnecessary suffering.
  • Weapons that cannot be directed against a specific military objective or whose effects cannot be limited in accordance with the provisions of international humanitarian law.
  • Weapons that cause widespread, long-term and severe damage to the natural environment.

On the basis of these four criteria, a number of specific weapons have been explicitly prohibited by international conventions, including anti-personnel mines, cluster munitions, blinding laser weapons, dumdum bullets as well as biological and chemical weapons. Some of these prohibitions are now part of customary international law.

The use of weapons in armed conflict is also restricted by the general rules and principles of international humanitarian law which stipulate, in particular, the measures that must be taken to minimise the impact of armed conflict on the civilian population and civilian objects. The principal rules of international humanitarian law governing the use of weapons are:

  • The obligation to distinguish between the civilian population and combatants and between civilian objects and military objectives
  • The prohibition on indiscriminate attacks
  • The obligation to respect the principle of proportionality
  • The obligation to take precautions to minimise the consequences of an attack for the civilian population

These rules are part of customary international law and therefore apply to all parties to a conflict, without distinction between governments and non-state armed groups and regardless of whether the state concerned has ratified a relevant international treaty.

The 1980 Convention and its five Protocols

The Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons of 10 October 1980 (CCW) is crucially important. Further to the framework Convention, three additional protocols prohibit or restrict the use of certain categories of weapon.

  • Protocol I on non-detectable fragments
  • Protocol II on mines, booby traps and other devices
  • Protocol III on incendiary weapons

Designed to be a dynamic instrument, the CCW has been revised to take account of the rapid development of weapons technology and methods of warfare since 1980. Its scope of application has so far been extended in three further protocols:

  • Protocol IV on blinding laser weapons (1995)
  • Amended Protocol II on mines, booby traps and other devices (1996)
  • Protocol V on explosive remnants of war (2003)

Further to the regulations on conduct in an armed conflict, the CCW also contains measures to be taken before the commencement of hostilities and after they cease. In 2001, the scope of the CCW was extended to cover non-international armed conflicts. Its extended scope of application takes account of changes in the nature of armed conflict in recent decades.

Switzerland has ratified the framework convention and its five protocols. It is actively involved in the work of government experts who are examining the potential regulation of types of weapons not yet covered by the CCW.

Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons which may be deemed to be Excessively Injurious or to have Indiscriminate Effects (with Prot. I – IV)

Protocol on Explosive Remnants of War (Protocol V to the 1980 CCW Convention), 28 November 2003

Conventions on cluster munitions and anti-personnel mines

Oslo Convention

On 17 July 2012 Switzerland ratified the Convention on Cluster Munitions, which was negotiated outside the framework of the UN. The convention entered into force in Switzerland on 1 January 2013. Switzerland had already signed the convention in 2008 and was a driving force in efforts to ban cluster munitions. The convention prohibits the development, production, use, transfer and stockpiling of cluster munitions. Following ratification, Switzerland adapted its War Material Act accordingly. In 2018, it destroyed its own cluster munition stockpiles, as required by the convention. More than 100 states have ratified the convention to date.

Convention on Cluster Munitions, United Nations Office at Geneva

Information on the Convention on Cluster Munitions

Ottawa Convention

Switzerland ratified the Ottawa Convention on 24 March 1998 and was one of the first states to do so. The convention was adopted in Oslo in 1997, also outside the framework of the UN. The convention bans the production, use, stockpiling and transfer of anti-personnel mines. More than 160 states have ratified it to date. State parties undertake to destroy their stockpiles of anti-personnel mines within four years of ratifying the convention and to destroy or ensure the destruction of all anti-personnel mines in mined areas under their jurisdiction or control within ten years. Switzerland destroyed the last of its stocks of anti-personnel mines in 1999.

Convention on the Prohibition of the Use, Stockpiling, Production and Transfer of Anti-personnel Mines and on their Destruction

Information on the Anti-Personnel Mine Convention