The Court decided that the Mann Act applied not only to purposes of coercion and prostitution but also to noncommercial consensual sexual liaisons.

The case has an historic place in American jurisprudence in that it was one of the first where the court embraced the idea of the "plain meaning rule".

This is a form of legislative interpretation that focuses strongly on the literal text of a statute.

The issue in the case that caused the Court to interpret using the plain meaning rule was whether the Mann Act's inclusion of the phrase "...or for any other immoral purpose..." included Caminetti's actions.

The Court found that Caminetti had been convicted of transporting a woman across state lines for an immoral purpose which, according to the majority opinion, was well within the plain meaning of the statute.