How can they be "the law of the land"? The legislative branch is the only branch empowered to make laws. And the executive branch is the only branch empowered to enforce them.
case law n. reported decisions of appeals courts and other courts which make new interpretations of the law and, therefore, can be cited as precedents. These interpretations are distinguished from “statutory law” which is the statutes and codes (laws) enacted by legislative bodies, “regulatory law” which is regulations required by agencies based on statutes, and in some states, the Common Law, which is the generally accepted law carried down from England. The rulings in trials and hearings which are not appealed and not reported are not case law and, therefore, not precedent or new interpretations. Law students principally study case law to understand the application of law to facts and learn the courts’ subsequent interpretations of statutes.