Congresswoman Hanabusa’s maternal great-grandparents were among the 200,000 Japanese who emigrated from Japan between 1885 and 1924 to work on the Hawaii sugar plantations. Her grandparents set the family roots in Waianae, on the Leeward Coast of Oahu, when they were born on and worked for the Waianae Plantation. Her maternal grandfather worked as a carpenter on the plantation and built and maintained the water flumes which carried water through the sugarcane fields from Makaha and Waianae Valley to Lualualei.

Her paternal great-grandparents were entrepreneurs who made and sold tofu to the plantation. Called Sampan Joe by some, her paternal grandfather was the plantation fisherman who sold his daily catch to the plantation store.

Both grandfathers were interned during the war – her paternal grandfather was sent to the mainland and Grandpa Muroda went to Honolulu, an internment camped on Oahu, because of their work as founders and organizers of the Waianae Hongwanji Mission. In 1977, her paternal grandfather was recognized by the Emperor of Japan with the 6th Class Order of the Sacred Treasure Award for his work in community service.

Congresswoman Hanabusa is the daughter of June and Isao Hanabusa. Isao and June ran a well known gas station in their hometown of Waianae. Her father worked for a kamaaina company, Gaspro, Inc., and until the day he died, served as a director for the successor entity, Lenakona, Inc. Running the family business consumed most of her parent's time, so Senator Hanabusa was raised by her maternal grandmother.

She graduated from St. Andrew’s Priory in 1969 then attended the University of Hawaii at Manoa where she received a Bachelor of Arts in Economics and Sociology in 1973, and Master of Arts in Sociology in 1975. In 1977, she earned her law degree from the William S. Richardson School of Law.

Congresswoman Hanabusa is an attorney with more than three decades of experience. She has championed the causes of labor, preserving and protecting the environment and stood up for communities she saw being bullied by private interest. Since 1993, she has been recognized by Honolulu Magazine’s as “One of Hawaii’s A+ Attorneys.” In 2004, she received the prestigious AV rating by Martindale-Hubbell, the highest rating any lawyer can achieve, and in 2009, the American Bar Association Commission on Racial and Ethnic Diversity presented Hanabusa with the Spirit of Excellence Award.

In November 1998, Congresswoman Hanabusa was elected to serve the people of the Twenty-First District as their State Senator. She was victorious in her first ever run for public office and immediately people recognized her talents and desire to improve the lives of Hawaii's working families.

She has been characterized by colleagues on both sides of the aisle as outspoken, independent and politically fearless. She played an instrumental role in the 1998 general election recount by getting the then-attorney general to apologize for implying that the voting problems in that election stemmed from the education level of Leeward Coast residents.

Her state legislative accomplishments include being named Vice-President of the State Senate and Vice-Chair of the Senate Committee on Ways and Means (2001-2002), Co-Chair of the Joint Senate-House Investigative Committee concerning the Felix Consent Decree (2001), Co-Chair of the Joint House-Senate Task Force on Ice and Drug Abatement (2003-2004), Chair of the Judiciary and Hawaiian Affairs Committee and Majority Leader (2003-2006). In November 2006, she was elected President of the Senate, the first woman to lead either house in the Hawaii legislature.

Congresswoman Hanabusa is married to Honolulu businessman John Souza. They have a 7 year-old Border Collie named Little, who enjoys a farm fresh egg every morning for breakfast, specially prepared by John.