A suit brought specifically for the establishment of an important legal right or principle.
The term test case describes a case that tests the validity of a particular law. Test cases are useful because they establish legal rights or principles and thereby serve as precedent for future similar cases. Test cases save the judicial system the time and expense of conducting proceedings for each and every case that involves the same issue or issues.
To illustrate, assume that Congress passes a law that makes using a cellular phone while driving a misdemeanor punishable by up to one year in jail and a fine of $10,000. Such a law would likely be challenged by a large number of cell phone owners, all of whom are in essentially identical circumstances and all of whom have the same arguments against the law. In such a situation, attorneys representing the plaintiffs might look for a case with a sympathetic set of facts with which to challenge the law. For example, they might select a case involving a driver who was charged with violating the law when she used her cell phone to request medical assistance for a family member. Other observant law firms would postpone or otherwise delay their own similar cases to wait for the outcome of the test case.
A test case need not concern a new law. Suppose, for example, an attorney or client is dissatisfied with the current state of a particular law and has strong arguments in favor of changing it. If the facts of the case give the attorney or client a good chance of prevailing, the case may be called a test case because the outcome would change the law for future persons in similar circumstances.
In some cases, a person may choose to violate an existing law to provoke a lawsuit, prosecution, or penalty. The person may then challenge the lawsuit, prosecution, or penalty and use the case to try and change the law through a judicial opinion. In Druker v. Commissioner of Internal Revenue, 697 F.2d 46 (2d Cir. 1982), cert. den., 461 U.S. 957, 103 S. Ct. 2429, 77 L. Ed. 2d 1316 (1983), for example, James O. and Joan Druker, a married couple, intentionally used the lower tax rates for unmarried individuals in computing their 1975 and 1976 INCOME TAX because they believed the federal tax scheme was unconstitutional under the EQUAL PROTECTION CLAUSE of the FOURTEENTH AMENDMENT. Before the INTERNAL REVENUE SERVICE (IRS) could take action against the Drukers, the Drukers filed suit against the commissioner of the IRS. The Drukers were unsuccessful, but had they received a favorable disposition, they would have succeeded in changing the law on federal taxation of married couples.