stateless or her country of nationality adopts a strict jus soli principle). However, these statistics indeed give some indications. 4. Solutions for Category E (1) Prevention From a prevention point of view, it is necessary to have changes in legislation and implementation of the current law which take into account, as a priority, the principles to avoid statelessness and to ensure legal certainty with regard to nationality, which are fundamental values unique to nationality law.184 Article 5(1) of the 1961 Convention on the Reduction of Statelessness provides that loss of nationality as a consequence of any change in the personal status of a person, such as marriage, termination of marriage, legitimation, recognition, or adoption, shall be conditional upon the possession or acquisition of another nationality. Such a “change in personal status” includes situations, e.g., where the family relationship which constituted the basis of a child’s acquisition of nationality was registered erroneously.185 Thus, a new legal provision should be created or the current law should be implemented such that the change in a person’s legal descent from a father or mother of Japanese nationality will not result in the him or her losing his or her Japanese nationality if such a loss consequently leads to statelessness. Furthermore, even if it does not lead to statelessness, the loss of nationality should be subject to certain restrictions. While there may be room for discussions as to what should be the point in time beyond which the loss is restricted, it is reasonable to prevent a loss of nationality at the least after a person has reached the age of majority. (To make the age of majority, 20 years of age, the time limit in legislation is consistent with the fact that acquisition of Japanese nationality under Article 3 of the Nationality Act is limited to persons less than 20 years of age. Restricting nationality “loss”186 for adults is also consistent with laws of many other States.) 187 Alternatively, if the avoidance of a 184 See the Supreme Court judgment on 22 November 2002, supra note 168. (“The call for prevention of uncertainty making it desirable for nationality acquisition to be decided as definitely as possible…”) 185 See Arakaki, supra note 2, p.58. 186 This kind of loss of nationality which is not specified by law is called “quasi-loss”, and it has been discussed internationally in recent years. That it should not lead to statelessness goes without saying; the retention of nationality should be continued in accordance with the principle of the prohibition of arbitrary deprivations of nationality, legitimate expectations, and the principle of proportionality. At the least, the loss should not be given a retroactive effect. Gerard-René de Groot and Patrick Wautelet, Chapter 4, “Reflections on quasi-loss of nationality from comparative, international and European perspectives”, in Sergio Carrera Nuñez and Gerard-René de Groot eds., European Citizenship at the Crossroads: The Role of the European Union on Loss and Acquisition of Nationality (Wolf Legal Publishers, 2015). 187 According to the European Convention on Nationality Article 7(1)(f) as well, a person’s nationality is not lost after reaching majority (18 years of age in many countries) even in cases where the preconditions for the automatic acquisition of nationality are no longer fulfilled. This is reflected in the internal law of many Contracting States. (Some countries designate a period even shorter than 18 years.) 87