Is my personal information safe?
The Census Bureau is required by Title 13 of the U.S. Code to keep your information confidential.
Personal census data CANNOT be shared for 72 years, even to law enforcement agencies or courts. The answers you provide are used only to produce statistics. Violating Title 13 is a federal crime, punishable by prison time and/or a fine of up to $250,000.
Only Congress can change the census confidentiality protections through the legislative process, and no lawmaker has proposed weakening the strong Title 13 protections. The Title 13 confidentiality provisions have been supported by the U.S. Supreme Court (Baldridge v. Shapiro, 455 U.S. 345 (1982)) and two Attorney General opinions.
(information from Asian Americans Advancing Justice)