Any measure taken under this principle must be strictly proportionate to the threat to the rights of others.181 This issue is most relevant to freedom of expression and is addressed in detail in that section of this manual. Impunity and amnesty The Human Rights Committee has consistently condemned statutes or Acts of Parliament that provide for impunity or amnesties for state officials who commit human rights violations. Particularly where the right to life or protection from torture have been violated, there is a duty to investigate and punish offenders. In their Concluding Observations on a number of states parties, the HRC and the CAT Committee have been critical of states with a culture of impunity.182 The CPT Committee adopted in 2004 general standards on combating impunity.183 In recent Concluding Observations, the HRC was particularly critical of the availability of the defence of necessity to persons charged with using improper techniques for interrogating suspected terrorists. It stated that The State party should review its recourse to the necessity defence […] It should ensure that alleged instances of ill-treatment and torture are vigorously investigated by a genuinely independent mechanism, and that those that are responsible for such actions are prosecuted.184 Additional concepts In addition to the ideas described above, there are several other concepts relevant to limiting rights in connection with counter-terrorism. These include: • Absolute necessity: This is the test to justify the use of lethal force under the right to life. It is the strictest test and requires the highest degree of supervision by the courts and justification on the part of those who exercise lethal force. • Strict necessity: This is the test used to limit the right to a fair trial and the right to liberty where the articles of human rights treaties protecting those rights permit limits to them. • Reasonable in the public interest: This test, often applied to property rights, requires states to show that any action limiting rights is both reasonable and in the public interest. This concept generally requires less judicial supervision than absolute necessity or strict necessity. Economic, social and cultural rights185 Civil and political rights are most often affected by counter-terrorism measures. However, the guarantee of economic, social and cultural rights is also of direct relevance. For example, 181 ECtHR, Lehideux and Isorni v. France, Case no. 55/1997/839/1045, 23 September 1998, para. 55. 182 CAT, Concluding Observations: Colombia, doc. CAT/C/CR/31/1, 4 February 2004, paras. 9-10. In its Concluding Observations regarding Spain in 1996, the HRC was concerned over the lenient sentences given to police officers convicted of human rights abuses. The Committee pointed out: “when members of the security forces are found guilty of [ill-treatment and even torture] and sentenced to deprivation of liberty, they are often pardoned or released early, or simply do not serve their sentences. Moreover, those who perpetrate such deeds are seldom suspended from their functions for any length of time”, doc. CCPR/C/79/Add. 61, 3 April 1996, para. 10. See also HRC, Concluding observations: Italy, doc. CCPR/C/79/Add.94, 18 August 1998, paras. 12-15. 183 Available at http://www.cpt.coe.int/en/docsstandards.htm. 184 Op. cit., note 131, Concluding observations of the Human Rights Committee: Israel, para. 18. 185 For further information, see A. Eide, C. Krause, A. Rosas (Eds.), Economic, social and cultural rights. A textbook, (2nd ed.) (Dordrecht-Boston-London, 2001). 76 Countering Terrorism, Protecting Human Rights