Nishimoto earned his Bachelor of Arts in sociology from the University of Hawaiʻi at Mānoa in 1997 and his Juris Doctor from its William S. Richardson School of Law in 2002.
As an undergraduate student, Nishimoto was accepted to a fellowship with the DC-based nonprofit Congressional Asian Pacific American Caucus Institute, later called the Asian Pacific American Institute for Congressional Studies.
Senator Daniel Inouye, he covered congressional hearings and compiled and distributed reports, sparking his interest in politics.
[4] As Judiciary Chair, Nishimoto helped push for the passage of House Bill 2071 which established the Law Enforcement Standards Board to regulate and investigate police officers.
At the end of the 2024 legislative session, Nishimoto announced he would leave the House of Representatives to run for a seat on the Honolulu City Council.