A good question from a 2301 student wrestling with this week's question on Coleman v. Maryland. The plurality decision in the case refers to this rule in its decision that Coleman's suit against Maryland - in federal courts - could not go forward. I'll try to provide a reasonable answer below. I also advise that you read the following article in the NYT for background.
First, "congruent" means the same as, and "proportional" means corresponding to. Here's a specific definition of the test from Wikipedia: "all legislation enacted under section 5 of the Fourteenth Amendment must be "congruent and proportional" to the unconstitutional harm it seeks to remedy." Congress can't create a right and use its enforcement powers to impose it on the states. Remember that the 14th Amendment provides the national government the ability to negate state actions that deny equal protection to "persons within its jurisdiction." Section 5 states the following: "The Congress shall have power to enforce, by appropriate legislation, the provisions of this article." For more info here read: Congressional Power of Enforcement.
As I understand it, the congruent and proportional test is a way to determine what enforecement mechanisms are and are not appropriate. Recently, it has been used often to determine whether civil remedies (lawsuits against the states in federal courts) are appropriate given the violation claimed by a litigant. Was someone denied a constitutional right - if so the suit goes forward - if not the suit is denied. So this test is tightly connected to the question of state sovereign immunity.
The lawsuit under review in US v. Morrison failed the test and was denied, but those reviewed in Tennessee v. Lane and Nevada v. Hibbs passed it, so they were upheld.
Second, this is an example of test that the Supreme Court establishes from time to time to not only justify a specific decision, but to it in a way that provides a (possible) guideline for future courts to rule on similiar cases. Other examples include the separate but equal doctrine, and the Lemon Test. If you feel ambitious you may want to read through this argument that the court is increasingly reluctant to establish such tests, and a comment here.
Third, the congruent and proportional test was established in the case of City of Boerne v. Flores. As it turns out - fortuitously - Boerne was a reaction to the passage of the Religious Freedom Restoration Act, which itself was passed in reaction to the Smith case we discussed earlier regarding peyote. This was the subject of a previous written assignment as you well know (or should know). RFRA attempted to revive a still different test - the Sherbert Test - which among other things stated that a compelling state interest must be furthered whenever a sincere religious belief is violated by the government.
The decision in Smith changed this rule and made religious liberty subject to generally applicable laws. In RFRA, Congress attempted to revive the more stringent standard, but the Boerne case allowed the court to strike that down - and in doing so they reminded Congress that the power to interpret the Constitution belongs to the court.
Finally, this test is controversial. Not everyone on the Supreme Court abides by it, or has the same attitude towards what rights may or may not exist beyond those that are clearly listed in the Constitution. In this case the question has to do with the extent of gender discrimination. This is a topic I hope 2301s are very familiar with by now.
I hope this review helps. Don't get too bogged down in this nuance as you complete the assignment.
Feeling ambitious? Read this: Congruence and Proportionality for Congressional Enforcement Powers: Cosmetic Change or Velvet Revolution?
