Nishikawa graduated from the Faculty of Law at the University of Tokyo and worked at the Ministry of Construction until 1975.
After the NFP dissolved in 1997, Nishikawa joined the Reform Club party led by Tatsuo Ozawa.
He remained a member of this party until his defeat in the June 2000 election, following which he returned to law practice.
During this time, Nishikawa was involved in the formation of the Financial Services Agency and the bail-out of the Long-Term Credit Bank of Japan.
[1] He was named as the member of the Executive Committee of Sidley LLP and served until December 2014.