document: 16 December 2015 Last updated at 00:22 GMT
  One bans women from marrying for six months after divorce, the other forces married couples to have the same surname.
  The laws are also linked to a rule that children born within that six months are considered to be the former husband's.
  The case was brought by three individual women and one couple in a civil partnership, who argue that the law is unconstitutional and discriminatory.
  Two lower courts have already ruled against them and public opinion on the questions is split.
summary: Japan's Supreme Court is due to rule on two 19th century family laws which critics say are sexist and out-of-date.