242 U.S. 470 (1917)
Caminetti v. United States is a pivotal Supreme Court case concerning the interpretation of the Mann Act, also known as the White-Slave Traffic Act of 1910.
Does the Mann Act apply solely to commercial vice activities involving prostitution, or does it also encompass non-commercial immoral activities?
The Mann Act prohibits the transportation of women across state lines for "prostitution, debauchery, or any other immoral purpose."
The Supreme Court held that the Mann Act applies to non-commercial immoral purposes, expanding its scope beyond prostitution.
Caminetti v. United States is significant as it illustrates the broad interpretive application of federal statutes based on legislative intent and language. Law students must understand this case to appreciate the interpretative methods used by courts when faced with statutory ambiguity—particularly the emphasis on plain meaning and legislative purpose. Furthermore, the ruling reflects evolving federal-state dynamics in regulating morality and underpins many future cases interpreting federal regulation of interstate matters.