Conditions for the acquisition of nationality

General principles

The right of states to determine their own jurisdiction and who its nationals are can be considered a generally recognised principle of public international law (Brownlie 2003: 373; Berber 1975: 374; Randelzhofer 2000: 501, 502). The principle, first codified in art. 1 of the 1930 Convention on certain questions relating to the conflict of nationality laws, has been repeated in numerous standard works and court decisions. The leading case has been the advisory opinion of the Permanent Court of International Justice in its 1923 advisory opinion in nationality decrees, issued in Tunis and Morocco: 'The question whether a certain matter is or is not solely within the jurisdiction of a state is an essentially relative question. It depends upon the development of international relations. Thus, in the present state of international law, questions of nationality are, in the opinion of the Court, in principle reserved domain.'

General acceptance of the principle does not mean that the freedom of states to regulate their nationality is unlimited. Since nationality has many international aspects relating to diplomatic protection, international responsibility and personal sovereignty, limits are set by the rights of other states as well as human rights considerations. The first aspect has already been noted by the German government in its reply to the Territory Committee for the Hague Codification Conference 1930. The German government stated that the application of the principle that questions relating to the acquisition or loss of a specific nationality shall be governed by the laws of the state whose nationality is being claimed or contested, should not go beyond the limits where the legislation of one state encroaches upon the sovereignty of another. For example, a state has no power, through a law or administrative act, to confer its nationality on all the inhabitants of another state or on all foreigners entering its territory.

Further, if the state confers its nationality on the subjects of other states without their request, when the persons concerned are not attached to it by any particular bond, such as origin, domicile or birth for instance, the states concerned will not be bound to recognise such naturalisation.

Similarly, the British representative pointed to the restrictions imposed by duties which a state owes to other states. It follows that the right of a state to legislate with regard to the acquisition and loss of its nationality and the duty of another state to recognise the effects of such legislation are not necessarily coincident.

The approach taken by the British government was also taken up by the International Court of Justice in the Nottebohm case. Attempts to distinguish municipal law effects of nationality from the international effects of nationality may raise some questions as to whether these aspects can be separated. Nevertheless, the principle that a state is not completely free to choose criteria for the conferment of its nationality and that other states may not recognise such conferment is undisputed.

A second set of limitations follows from human rights considerations and related concepts even before human rights entered the sphere of public international law. The 1930 Hague Convention contained provisions on reducing statelessness. Expatriation, therefore, was not to result in denaturalisation, unless the person in question possessed or required another nationality; rules were laid down in subsequent international treaties and recommendations of the Council of Europe regarding the nationality of women as a consequence of marriage, dissolution of marriage or a change in their husband's nationality.

The rights of children of unknown or stateless parents and foundlings to receive the nationality of the state of birth or the state where they were found had already been laid down in the 1930 Hague Convention.

All these treaties and recommendations did to some extent influence existing international law on the acquisition of nationality although - as the European Convention on Nationality indicates – there is considerable divergence as to the rules and practices of the modes of acquisition as well as the loss of nationality.

Chapter 2 of the European Convention describing the general principles relating to nationality therefore very cautiously states that the rules on nationality of each state party shall be based on the following principles:

- everyone has the right to nationality,

- statelessness shall be avoided,

- no-one shall be arbitrarily deprived of his or her nationality,

- neither marriage nor the dissolution of a marriage between a national of a state party and an alien, nor a change in nationality by one of the spouses during the marriage shall automatically affect the nationality of the other spouse.

The Convention confirms the principle of sovereignty by stating in art. 3 that each state shall determine under its own law who are its nationals. This law shall be accepted by other states in so far as it is consistent with applicable international conventions, customary international law and the principles of law generally recognised with regard to nationality. The wording 'shall be based' is intended to indicate an obligation

to regard the principles as the basis for national rules on nationality. On the other hand, the principles are not to be taken as absolute. Their precise content is to be determined by more detailed rules laid down in the Convention and elsewhere. Therefore, concerning the right to a nationality, the Explanatory Report makes clear that the right to any particular nationality is determined by the rules on nationality of each state party, consistent with art. 3 of the Convention. 1.2.2 Acquisition by descent (iure sanguinis) or by birth on territory (iure soli)

Acquisition of nationality by descent from a national or by birth within state territory are the predominant modes of acquisition of nationality. Scarcely any dispute exists that the two criteria are sanctioned by customary international law as commonly recognised criteria which must be recognised by other states as bases for acquisition of nationality (see Panhuys 1959: 160; Brownlie 2003: 378). A survey of states' practice leads to the conclusion that the legal systems of states are based either on ius sanguinis or ius sanguinis along with ius soli. It seems that these criteria are not used interchangeably. There is no state which bases its nationality law exclusively on ius soli. The systems differ only to the extent to which ius soli or other criteria are accepted as equally valid modes of acquisition of nationality. The systems may also differ in terms of the extent to which birth abroad may limit the acquisition of nationality by descent.

The only exception seems to be the acquisition of nationality of the Vatican City state, where nationality is acquired only by holding office and residing in the Vatican City. The particular circumstances of this case are hardly suitable to refute the argument that there is a widespread acceptance of the principle of the acquisition of nationality of a child, one of whose parents possess the nationality of that state party at the time of the child's birth (art. 6, para. 1 ECN).

Although, originally, the rule in some systems had been limited to acquisition of the nationality of the father, with the development of rules on the prohibition of discrimination based on gender, the nationality laws of European states were uniformly adapted to the equal treatment requirement, extending the ius sanguinis principle to the mother of the child.

Problems may arise in cases of the acquisition of nationality in mixed marriages and concerning children born out of wedlock. The Council of Europe's Parliamentary Assembly Recommendation 1081 regarding problems of nationality in mixed marriages40 recommends that children born from mixed marriages should also be entitled to require and keep the nationality of both of their parents. The 1998 Recommendation implies a certain change of attitude regarding the position taken eleven years earlier in the Council of Europe Committee of Ministers Resolution 7713.41 The Committee had recommended the insertion of provisions in national legislation for the purpose of avoiding dual nationality resulting either directly or indirectly from descent or resulting from the place of birth. States should grant the right to their nationals who hold another nationality to renounce their nationality and permit their nationals who acquire another nationality to make a declaration in favour of their new nationality. The different wording of the later Recommendation, as well as art. 14 of the European Convention on Nationality, indicate a shift of attitude towards acceptance of dual nationality by children having different nationalities acquired automatically at birth. Under art. 14, para. 1 ECN, state parties shall allow retention of these nationalities. No reservation so far seems to have been entered against this provision by any contracting state. Art. 6, para. 1 ECN does not distinguish between married and unmarried mothers concerning the acquisition of nationality by descent. The only exception is made for internal law restrictions as regards children born abroad. Whether, under the general principle of non-discrimination on the grounds of sex, the same applies to the father may be doubtful. Art. 6 already provides for a distinction with respect to children whose parenthood is established by recognition, court order or similar procedures. Each state party in this case may stipulate that the child acquires that nationality following the procedure determined by its internal law. Regarding this provision, Austria has declared that the term 'parent', used in art. 6 of the Convention, does not include the father of children born out of wedlock according to the Austrian legislation on nationality. While the requirement of a special procedure seems to be justified by the different conditions under which parenthood is established ('mater semper certa est') the total exclusion of a father with regard to the acquisition of nationality for children born out of wedlock seems to be a doubtful proposition in the light of art. 5 on non-discrimination.

Acquisition by birth on the territory (ius soli) is equally recognized as a criteria for the conferment of nationality. To varying degrees, the Nationality in public international law and european law laws of a large number of states rest on both principles. In Europe, ius soli as an additional reason for acquisition of nationality for second generation migrants has received growing support. The second protocol amending the 1963 Convention on the Reduction of Cases of Multiple Nationality has introduced a rule whereby nationals of a contracting party, acquiring the nationality of another contracting party on whose territory they were either born and were resident or have been ordinarily resident for a certain period of time, may accept dual nationality.

Although the focus is on a broader acceptance of dual nationality, the protocol is based on the assumption that migrants who had settled permanently in the Member States of the Council of Europe, particularly in the case of second generation migrants, should acquire the nationality of the host state ex lege.

The rule, however, did not receive general approval and the second protocol was only ratified by a small number of contracting states. The European Convention on Nationality is somewhat more careful in providing that each state party shall 'facilitate' in its internal law the acquisition of its nationality for persons who were born on its territory and reside there lawfully and habitually - thus leaving it up to the states to either introduce ius soli or provide for naturalisation. An obligation to grant ex lege acquisition at birth is only provided for children born on the territory of a contracting state who do not acquire another nationality at birth (see art. 6, para. 2).

Conferment of nationality to persons born on territory in countries applying a general ius soli rule is not usually dependent upon the length of time a person has spent on the territory of birth of a child or upon the residence permit acquired. There are, however, certain limitations generally accepted in customary international law to the principle. One exception is the rule that children of persons with diplomatic immunity do not acquire the nationality of the state where they are born. The rule is applied to diplomats covered by the Vienna Convention on diplomatic relations of 18 April 1961, as well as to persons enjoying diplomatic immunity under the Vienna Convention on consular relations of 24 April 1963.42 Another exception is sometimes made with respect to the children of persons exercising official duties on behalf of a foreign government (see Brownlie 2003: 380). More recently, the tendency is towards somewhat limiting the application of the ius soli rule for persons having illegally entered the territory or having entered only for the purpose of a temporary stay. In reaction to the European Court's judgement in the Chen case discussed in section 1.3 above, Ireland, a traditional ius soli country, voted by a clear majority in a referendum for a restriction of the ius soli rule to persons possessing a residence permit.

States applying a ius soli concept sometimes also confer nationality ex lege on children born on vessels or aircraft flying their flag. It appears that the extension of ius soli to vessels or aircraft is a consequence of a somewhat obsolete concept of vessels and aircraft as the fictitious territory of the state whose flag they fly. It is difficult to see an actual link for conferring nationality since there is no genuine connection between the person born and the state. However, the same criticism could be made with regard to a temporary visit to a state in a globalised world with millions of travellers.

The ius soli concept is considered by some writers as a preferable system, relatively simple in outline. The principle may have had its justification in the nineteenth century and first half of the twentieth century since, in principle, only people intending to emigrate were travelling abroad and giving birth to children abroad (for a different view see Brownlie 2003: 379). In a highly mobile world, however, the mere fact of birth within the state territory, which may be either accidental or intentionally chosen by parents, and the mere purpose of 'nationality shopping' can hardly be considered a sufficient link for the attribution of nationality compared, for instance, to other criteria which are generally used for conferring nationality by naturalisation. However, there are no indications that the intentional use of nationality laws in order to acquire nationality during temporary or illegal residence does establish nationality that is invalid in international relations. In the Chen case, the European Court of Justice has confirmed that it is up to each Member State to determine the conditions for acquisition and loss of nationality. With respect to Community law, however, the reservation is that the competence of Member States is to be exercised with respect to the requirements of Community law. The Court was in no doubt that Irish nationality with effect for other Member States of the European Union had been acquired by the child of a Chinese national travelling to Ireland for the purpose of giving birth.

In line with the principle that each state shall determine, under its own law, who are its nationals, various other criteria are used in state practice and recognised by international law for the conferment of nationality.

Sometimes entry into state service will result in an acquisition of nationality ex lege. Sometimes nationality is also acquired automatically upon a change in civil status such as adoption, legitimisation, affiliation or marriage to a national of that state (see Randelzhofer 2000: 504). The European Convention, in art. 6, para. 4, does mention some of these categories in the context of a duty to facilitate the acquisition of nationality, leaving it, however, to the contracting states whether facilitation is to be achieved by naturalisation or by conferment ex lege.

With regard to the acquisition of nationality of spouses, the trend goes clearly against an automatic conferment of the nationality of the Nationality in public international law and european law other spouse. The Council of Europe Resolution of 1977 on the nationality of spouses of different nationalities44 has not only confirmed the principle of legal equality between the sexes which should lead to equal treatment of men and women with regard to the conditions under which one of the spouses can acquire the nationality of the other, but has also recommended the possibility for spouses who so wish to acquire the nationality, under a privileged procedure, of the husband or the wife. The principle that marriage does not result in an automatic change of nationality, which had never been applied to men, can now be considered a general principle of law. It is implicit in art. 6, para. 4 ECN.