Article 2 of the European Convention on Human Rights states that the "deprivation of life shall not be regarded as inflicted in contravention of this article when it results from the use of force which is no more than absolutely necessary: a) in defence of any person from unlawful violence; b) in order to effect a lawful arrest or to prevent the escape of a person lawfully detained; c) in action lawfully taken for the purpose of quelling a riot or insurrection.

Article 3 of the Code of Conduct for Law Enforcement Officials, adopted by the United (UN) Nations General Assembly in 1979, states that law enforcement officials (23) ''may use force only when strictly necessary and to the extent required for the performance of their duty [and] no force beyond what is authorized in the circumstances may be used".

The Code further states, "In no case should the use of force which is disproportional to the legitimate objective be achieved". The commentary to this Article "emphasizes that the use of force by law enforcement officials should be exceptional".

Article 10 of the International Covenant on Civil and Political Rights (ICCPR), to which the United Kingdom is a party and thus bound to comply, provides that "all persons deprived of their liberty shall be treated with respect for the inherent dignity of the human person".

Article 7 of the ICCPR, the UN Convention against Torture and other Cruel, Inhuman or Degrading Punishment and Article 5 of Universal Declaration of Human Rights all state that "no one shall be subjected to torture or to cruel, inhuman or degrading punishment".

Article 6 of the ICCPR states, "Every human being has the inherent right to life [and] no one shall be arbitrarily deprived of his life".

Article 12 of the UN Convention against Torture and other Cruel, Inhuman or Degrading Treatment or Punishment calls for a "prompt and impartial investigation" of allegations of ill treatment.

Source: Amnesty International