1. Alderman v. United States and Soldal v. Cook County, 506 U.S. 56 (1992).
2. Fourth amendment of the U.S. Constitution.
3. Hanzai Sousa no tameno Tsushin bouju ni kansuru Ho [Act on Wiretapping for Criminal Investigation], Law no. 137 of 1999. (Japan).
4. HIRAMATSU,Tsuyoshi, KOJIN JOUHUO HOGO [Protection of personal information] Japan: Gyosei, 1999, pp. 47, 108, 195.
5. House of Representatives of Japan, Question by Member of House of Representatives Takeshi Shina (7. December, 2017).