were in foster care, more than 3,500 persons incarcerated in Czech prisons, and more than 2,000 others who could not determine or exercise their nationality. Following advice provided by UNHCR and the Council of Europe, the Czech government began to loosen its restrictions on the acquisition of citizenship. In April 1996, the Czech legislature adopted an amendment to the Citizenship Act that gave the Ministry of the Interior the discretion to waive the requirement for a clean criminal record for applicants who were or had been Slovak citizens who had continuously resided in the Czech Republic and possessed official proof of such residency. Then, in 1999, the Czech legislature passed another amendment that allowed citizens of the former Czechoslovakia who had permanently resided in the territory that became the Czech Republic, but who did not possess an official residency permit, to become citizens of the Czech Republic. Under the amendment, these persons were allowed to prove their residency through work and/or housing contracts and/or witnesses. They, too, were not required to have a clean criminal record. Gradually, through the concerted efforts of UNHCR, NGOs and the Czech authorities, those former Czechoslovaks who have resided permanently in the Czech Republic since the dissolution of the federation have been granted unlimited access to citizenship of the Czech Republic. Causes linked to discrimination or arbitrary deprivation of nationality Discrimination One of the principal constraints on State discretion to grant or deny nationality is the proscription against racial discrimination. This principle is reflected in the Convention on the Elimination of all Forms of Racial Discrimination and in many other instruments. In its General Recommendation on Discrimination against Non-citizens of 1 October 2004, the United Nations Committee on the Elimination of Racial Discrimination stated that “deprivation of citizenship on the basis of race, colour, descent, or national or ethnic origin is a breach of States’ obligations to ensure non-discriminatory enjoyment of the right to nationality.” However, sometimes individuals are unable to acquire the nationality of a particular State despite having strong ties to that State – ties that, for other persons, would be sufficient to trigger the granting of citizenship. Discrimination based on race, colour, ethnicity, religion, gender, political opinion, or other factors can be either overt or created inadvertently in the laws or as they are implemented. Laws may be said to be discriminatory if they contain prejudicial language or if the result of their application is discrimination. To avoid this problem: • 38 Ensure that the principle of non-discrimination relating to nationality is enshrined in the constitution and in laws relating to nationality and ensure, through administrative and judicial decisions, that the principle is implemented.