Amendments to the passed a plenary session of the House of Councillors on June 13 with a majority vote of eight ruling and opposition parties.

One of the key features of the amendments is to automatically lower the voting age from "20 years or older" to "18 years or older" four years after entering into effect. Motions to amend the constitution require 2/3 supermajorities of both the House of Councillors and the House of Representatives. Approval of the amendments will pave the way for a national referendum on a constitutional revision when and if the Diet proposes a motion.

On June 11, the House of Councillors Commission on the Constitution adopted a supplementary resolution calling for the election voting age stipulated in the Public Offices Election Act to be lowered to "18 years or older" to go in effect no more than two years after its passage. This would change the voting age in advance of adjusting the "adult age" definition in the Japanese civil law (currently 20 years). The resolution also calls for measures to enhance and deepen constitutional education in the schools.

A total of eight parties: the LDP, New Komeito, DPJ, Japan Restoration Party, Your Party, Unity Party, People's Life Party and New Renaissance Party -- all seek to lower the referendum voting age and the election voting age simultaneously.. The parties agreed in April to gather a team to examine various issues and will work to speed up the discussions going forward.