The United States is a federation of 50 states. Its governing body combines a centralized federal body and 50 state governments. At both levels, each branch of the government makes law that conforms to the requirement of the rule of law. They are both procedural and substantive restraints. The rule of law requires any legal system to be stable.

Only stable systems can aspire to satisfy the requirements of generality and prospectivity. So, once an assembly has properly enacted a statute, absent an aggrieved party, there is no judiciary recourse, and absent judiciary process, it often makes more political sense to leave it untouched. The sign of a good government is the diversity of its norms that cover as many political interests as possible. Norms that may not necessarily achieve any regulatory effect, and thus may not be an example of legal normativism, may, nevertheless, represent specific interests uncovered by other statutes. Through such norms, the legal system is able to represent a large constituency, which is needed in any representative democracy. Again, they will rarely be changed.

The next examples should also introduce you to another important aspect of the American legal heritage: the interplay between the legislative and the judicial branches.
For more than a century, the judiciary has been at the pinnacle of the American legal system deciding what the Constitution is and what rules violate the Constitution. The American judiciary is in charge of interpreting the law enacted by the legislative branch, and sometimes courts minorities-have overruled statutes that mirror majoritarian positions. Thus, you always need to make sure that your legal research covers court decisions. The examples below illustrate that to the extent each lawmaking goven1mental branch respects procedural restraints and exercises publicly justifiable power, the norms they make will rarely be questioned or changed, irrespective of their social merit as long as their content does not defy the values promoted by the rule of law.

This observation will help you understand why some U.S. Supreme Court decisions are still good law or why others are being incrementally changed. When you do legal research, the above observation will help you remember that while you constantly need to update your results often, there is nothing out there affecting your research results. The next three examples will hopefully make it easier for you to see the interplay between legal stability and change, which is only another facet of the interplay between the abstract and concrete facet of American law. They should both emphasize the need for updating and the difficulty of ending your research when you may not find anything new to add. Sometimes, you feel that there should be something more and there is not. Developing a sense of confidence in your research results is also part of the complexities of American legal research. When you become aware of these idiosyncrasies of the American legal system you will also understand how to better strategize your legal research.