When it comes to ambiguous relationships, dealings between Congress and the court can be more confusing than those between a typical hot and then cold again couple. The Constitution clearly defines the relationship between Congress and the executive branch, but shies away from such clarity when it comes to the relationship between Congress and the court. The Supreme Court holds the power to interpret laws and declare them unconstitutional under the principle of judicial review. While Congress doesn't technically have the power to overrule a Supreme Court decision, it can take actions to lessen, or even negate, the effect of a court ruling. Congress can thereby render the court's interpretation obsolete, either by passing a new law or amending the old law to better achieve its original intent.
Checks and Balances
The framers of the Constitution designed the U.S. government so that each branch had a check on the others. In this way, no one branch would have absolute authority. Judicial review is the main way the Supreme Court can check the legislative branch's power. If a case before the court raises a constitutional question, the justices may decide a law violates the Constitution. Congress then has the power to pass another law to override that court ruling. Of course that law, if challenged, would be subject to further judicial review.
A Question of Precedent
Congress can't eliminate court precedent. While Congress may pass a new law that changes the impact of the court's decision, the precedent remains in effect. For example, in 1986 the Supreme Court ruled that a federal civil rights law that protected people with disabilities from discrimination did not apply to the airline industry. However, Congress meant for that law to apply to airlines. Congress responded to the decision by passing a new law, the Air Carrier Access Act, that applied specifically to air travel. While this had the effect of protecting the rights of disabled people traveling by air, it didn't overturn the court's decision. The earlier law still doesn't apply to the airline industry.
In deciding new cases, the court is bound by precedent established in cases decided previously. Sometimes, these precedents combined with the precise language of a law lead the court to a decision it doesn't like, or that it thinks probably goes against Congress' intent in making the law. When this happens, the court's majority opinion may include an invitation to the legislature to either amend the law, or to pass a new law that fixes the problem.
The Long Way Around
Drafting and passing a new law can be a time-consuming process, but it certainly takes less effort than amending the Constitution. A constitutional amendment requires a two-thirds majority in both the House and the Senate. If it passes this hurdle, the amendment is sent to the state legislatures. The amendment doesn't become an official part of the Constitution until 75 percent of the states approve it. Constitutional amendment isn't always necessary, however, to correct judicial interpretations that go against congressional intent. For example, Congress passed the Civil Rights Act of 1991 after several Supreme Court decisions illustrated how prior civil rights laws didn't have as broad a scope as the legislature intended. The act negated as many as nine court opinions, including five decisions handed down just two years earlier.