To cite legal documents, APA defers to the most recent edition of The Bluebook: A Uniform System of Citation (Cambridge: Harvard Law Rev. Assn.). In text cite the name of the case (italicized) and the year of the decision.
Example:
Synder v Phelps et al., 562 US _____(2011)
Unenacted federal bills and resolutions
Example:
Removing the deadline for the ratification of the equal rights amendment, H. J. Res. 47, 112th Cong. (2011-2012)
Sample reference to a statute in a federal code
Example:
Family and Medical Leave Act of 1993, 29 U.S.C. §§ 2601–2654 (2018).