Legislation now before the Lower House seeks to amend the Civil Code and related laws to lower the legal age of adulthood from 20 to 18. Like the earlier amendment of the Public Offices Election Law to allow 18- and 19-year-olds to vote beginning in the 2016 Upper House election, this policy measure is aimed at promoting social participation by more youths as the nation's population shrinks and rapidly ages. Since the age of 18 is defined as the threshold of legal adulthood in many other countries, the proposed lowering of the age of adulthood does not appear to face strong public objections. Still, it marks a change in the legal definition of adults that has continued for more than 140 years since the early Meiji Era, and sufficient steps should be taken to avoid any social confusion resulting from the amendment.

Once the legislation is enacted, the government plans to implement the new law in April 2022. Meanwhile, a governmental liaison council comprising officials from the Justice Ministry, the education ministry and the Consumer Affairs Agency will try to identify potential problems that the lower age of adulthood could give rise to and spell out possible countermeasures.

The proposed Civil Code revision lowers the adulthood age to 18 and raises the minimum age at which a woman can marry from 16 to 18 — on par with men. As a result, the provision mandating parental consent for the marriage of a minor will be unnecessary and eliminated. There are 22 related laws to be amended with the change in adulthood age. While people can start applying for a 10-year passport and be eligible to become judicial scriveners and certified public accountants at the age of 18, the ban on the purchase of alcohol, tobacco and tickets for publicly run gambling such as horse racing by people under the age of 20 will be maintained on the grounds of preventing health damage and gambling addiction among youths.