The parents are an American father and a Japanese mother who were married and living in the United States. In July 2014, the mother removed their four children to Japan when the elder twins were 11 years and 7 months old and the younger twins 6 years and 5 months old. In breach of her promise to return to the United States, the mother wrongfully retained the children in Japan. The 1980 Hague Child Abduction Convention entered into force between the United States and Japan on 1 April 2014.
The father petitioned the Japanese courts for return of the children in August 2015. The Osaka High Court accepted the petition and ordered the return of all four children, holding that return was in the interests of the elder mature twins despite their objection to being returned, and that there was no grave risk of placing the younger twins in an intolerable situation by returning them to the United States. The return order became final and binding in January 2016. However, all the children continued to stay in Japan. In September 2016, execution of the return order by substitute was attempted, but failed.
Meanwhile, the father’s living conditions in the United States noticeably deteriorated. The family home was put to auction in February 2016, and he moved into a room at an acquaintance’s house in August of that year. The mother applied to the Japanese courts to modify the return order and dismiss the father’s petition for return of the children pursuant to Article 117(1) of the Hague Convention Implementation Act (?Japanese Act”), on the grounds that it would be inappropriate to return the children in the light of this change in circumstances. The Osaka High Court granted the mother’s application in February 2017.