or herself as the parent of a child, including for the purposes of the operation of the nationality law. g. Consider the full array of available evidence in helping to establish the parent–child relationship to ensure the recognition of nationality, and do not discount evidence but rather recognize the facts established by documentation that is issued by non-State entities. Allow non-documentary forms of evidence in the absence of birth registration. h. Given its invasiveness, use DNA testing only as a last resort for establishing the parent–child relationship. If DNA testing is required, make it accessible, removing barriers to access, both physical and practical. DNA test results, once they have served the purpose of establishing a biological connection between the child and his or her parent or parents, should be destroyed. cumstance that is found to be seriously prejudicial to the vital interests of the State or engagement in the military service of a foreign State, that measure should be imposed only following a careful assessment of necessity and proportionality, and with full respect for procedural safeguards to guarantee due process, including transparency and an effective appeals mechanism. l. Never deprive a child of his or her nationality. m. Ensure that denial or deprivation of nationality of a parent does not result in derivative loss for the child or otherwise undermine the rights of the child, including the right to family life. Children cannot be discriminated against based on the actions of a parent or family member. n. Prevent statelessness in all cases. Birth registration i. Ensure all children born on State territory have access to immediate birth registration. Birth registration is essential to protect a child and determine his or her identity and nationality. Children should also be provided with a birth certificate. Deprivation of nationality j. Avoid the use of deprivation of nationality as a counter-terrorism measure. This is increasingly understood to be counterproductive to security aims and is likely to be considered arbitrary under international law. k. In the event of the use of deprivation of nationality in the narrow cir- 49.