Born in Tokyo on October 20, 1958, attended Shiba Gakuen (Shiba Junior High and Shiba High School) and then entered Waseda University's Faculty of Political Science and Economics (belonged to the cheering club while attending school). Second year student of Matsushita School of Government and Economics. The first secret book published by Morihiro Hosokawa, member of the House of Councillors. In 1993, he was elected leader of the House of Linguists in the 40th general election. In 2007, he was elected chief in the 21st Notification Councilor's Office election. In 2009, he was appointed Deputy Minister of Health, Labor and Welfare under Hatoyama Uchimasa; in 2010, he was reappointed as Deputy Minister of Health, Labor and Welfare under Suganaichi; in 2011, he was appointed Deputy Chief Cabinet Secretary Uchimasa under Noda Uchimasa; in 2012, he became Minister of the Environment, Minister in charge of nuclear power plant accident containment and prevention of recurrence, and Minister in charge of Special Missions of the Prefectural Government; re-elected in 2013 in the 23rd Notification Council election. Served as Chairman of the National Basic Policy Committee and Chairman of the Land, Infrastructure, Transport and Tourism Commission. Re-elected in the 25th House of Councilors election in 2019. Served as Chairman of the House of Councilors of the Democratic Party of Japan and Chairman of the Environment Committee. 2022-2025: Vice-chairman of the House of Councilors, re-elected in the 27th House of Councilors election in 2025
〇Chairman of the Constitution Review Committee of the Board of Counselors
〇Notification of 4 members of the House of Representatives
