Mr. Kikawa was assigned as a public prosecutor in April 2000. During the first seven years of his career, he oversaw every kind of criminal investigation, such as mafia-related crimes, serious fraud and crimes committed by U.S. servicemen. During this period, he joined an internal investigation team at the Ministry of Justice that probed a prisoner's death that was caused by prison officers. He also joined an investigation team that handled a case concerning a world- renowned car manufacturer's defective products. He was assigned exclusively to that case for a year and four months. In addition, he participated in the International Training Course on Transnational Organized Crime at the United Nations Asia and Far East Institute for the Prevention of Crime and the Treatment of Offenders (UNAFEI) in 2006.

Mr. Kikawa transferred to the Ministry of Justice, Immigration Bureau in April 2007. He handled amnesty issues and refugee recognition issues during his first year there. He was assigned as a drafter of the amendment of Immigration Law at the beginning of his second year at the Immigration Bureau, and the amended law was passed by Congress in 2009. During his three years in the Ministry of Justice, he also supervised administrative depositions related to information disclosure.

After working for the Ministry of Justice, Mr. Kikawa returned to the Tokyo Prosecutors' Office in April 2010, and was assigned as the Chief Prosecutor of Medical Matters. He specialized in medical malpractice manslaughter cases and the violation of medical and pharmaceutical regulations. At the same time, he handled fatal accidents caused by construction disasters.

Mr. Kikawa joined Nagashima Ohno & Tsunematsu in April 2012. He provides advice to a wide range of clients, including pharmaceutical companies, medical device manufacturers, car manufacturers, electrical device manufacturers, industrial machine and parts manufacturers, food and beverage manufacturers, telecommunications carriers, IT companies, banks and brokerage firms.