Nevertheless, Israel's sovereign right to take all appropriate steps to prevent violence against its citizens is not disputed. However, security measures must be taken in accordance with internationally recognized legal norms and principles.26 For example the Siracusa Principles27 establish that a state will not use “more restrictive means than are required for the achievement of the purpose of the limitation”,28 and that the “laws imposing limitations on the exercise of human rights shall not be arbitrary or unreasonable”.29 More specifically, the Principles provide guidelines regarding limitations applied on the basis of national security. They establish that states cannot impose limitations merely to prevent relatively isolated threats to law and order; that national security cannot be used as a pretext for imposing arbitrary limitations; and, especially, that “the systematic violation of human rights undermines true national security and may, in fact, jeopardize international peace and security. A state responsible for such violation shall not invoke national security as a justification for measures aimed at suppressing opposition to such violation or at perpetrating repressive practices against its population”.30 Limitations on the Freedom of Movement Outside the West Bank One of the most prominent measures undertaken by Israel under the premise of “security” has been the construction of the Annexation and Segregation Wall. But if the Wall was in fact built to prevent Palestinians from entering Israel without prior clearance from the Israeli authorities, then it is very unlikely that, more than a decade after construction of the Wall began, tens of thousands of Palestinians continue to work inside Israel without proper permits (illegal according to Israeli law) but with the explicit knowledge of Israeli authorities. In the first quarter of 2015, 39,300 Palestinians were 26 Palestinian Centre for Human Rights, “The Israeli Policy of Closure: Legal, Political, and Humanitarian Evaluation”, 20 December 1996, chapter 2, available at: http://www.pchrgaza.org/files/S&r/English/ study6/Chapter%20Two.html 27 The Siracusa Principles were adopted in May 1984 by a group of international human rights experts to consider the limitation and restriction provisions of the ICCPR. See United Nations, Economic and Social Council, “Siracusa Principles on the Limitation and Derogation Provisions in the International Covenant on Civil and Political Rights”, U.N. Doc. E/CN.4/1985/4, Annex (1985), Available at: https://www1.umn.edu/humanrts/instree/siracusaprinciples.html; Lawyers’ Rights Watch Canada, “International Human Rights Law: Non-Treaty Standards”, located December 2015, available at:http:// www.lrwc.org/education/international-law/non-treaty-standards/ 28 UN Commission on Human Rights, “The Siracusa Principles on the Limitation and Derogation Provisions in the International Covenant on Civil and Political Rights”, 28 September 1984, E/CN.4/1985/4, Principle 11, available at:http://www.refworld.org/docid/4672bc122.html 29 Ibid. Principle 16 30 Ibid. Principle 32 15