A/HRC/4/26 page 12 43. The Special Rapporteur finds these pronouncements consistent with the established jurisprudence of international human rights bodies interpreting the non-discrimination guarantees of the ICCPR and the ICERD, as well as with that of regional bodies on the respective norms contained in regional human rights treaties. According to this jurisprudence, a difference in treatment on the basis of a criterion such as race, ethnicity, national origin or religion will only be compatible with the principle of non-discrimination if it is supported by objective and reasonable grounds.24 44. The Special Rapporteur takes the view that terrorist-profiling practices that involve distinctions according to a person’s presumed “race” cannot be supported by objective and reasonable grounds, because they are based on the wrongful assumption that there are different human races and, therefore, inevitably involve unfounded stereotyping through a crude categorization of assumed races, such as “white”, “black” and “Asian”. Test of legitimate aim and proportionality 45. As far as distinctions according to national or ethnic origin and religion are concerned, the following two sub-tests are generally applicable to determine the existence of an objective and reasonable justification. First, the difference in treatment must pursue a legitimate aim. Second, there has to be a reasonable relationship of proportionality between the difference in treatment and the legitimate aim sought to be realized. 46. As far as the first requirement is concerned, the aim of law-enforcement practices that are based on terrorist profiling is the prevention of terrorist attacks. In the view of the Special Rapporteur, this constitutes a legitimate and compelling social need. 47. The decisive question is therefore whether terrorist-profiling practices, and the differential treatment they involve, are a proportionate means of achieving this aim. In assessing proportionality, the Special Rapporteur believes that it is important to consider, first, whether terrorist-profiling practices are a suitable and effective means of countering terrorism and, second, what kind of negative effects these practices may produce. 48. In order to serve as a suitable and effective tool of counter-terrorism, a profile would need to be narrow enough to exclude those persons who do not present a terrorist threat and, at the same time, broad enough to include those who do. However, terrorist profiles that are based on characteristics such as ethnicity, national origin and religion are regularly inaccurate and both over- and under-inclusive. 24 Human Rights Committee, general comment No. 18: Non-discrimination (1989), para. 13; Human Rights Committee, Broeks v. The Netherlands, communication No. 172/1984 (CCPR/C/OP/2), para. 13 (1990); Belgian Linguistics Case (No. 2) (1968) 1 EHRR (European Human Rights Reports) 252, para. 10; Proposed Amendments to the Naturalization Provisions of the Constitution of Costa Rica, Advisory Opinion OC-4/84, Inter-American Court of Human Rights (Ser. A) No. 4 (19 January 1984), para. 57.