A native of Setagaya, Tokyo, and graduate of Tamagawa University, he was elected to the House of Councillors for the first time in 1999, a position he retained until his death in 2020.

[1] Following the loss of the Democratic Party of Japan to the Liberal Democratic Party in the 2012 Japanese general election, Noda and his Cabinet, including Hata, were succeeded by Shinzo Abe and his Cabinet on 26 December 2012.

[4] In all, he served as a legislator for five terms and was the initial Secretary-General of the Upper House caucus of the CDP at the time of his death in December 2020.

[5] On 15 August 2012, Hata, along with National Safety Commissioner Jin Matsubara became the first cabinet ministers of the DPJ to openly visit the controversial Yasukuni Shrine since the party came to power in 2009.

[8] Hata was a supporter of agricultural protectionism in regards to fair trade agreements such as the Trans-Pacific Partnership.