Legal Definitions - case-or-controversy requirement

The case-or-controversy requirement is a constitutional rule that states that for a federal court to hear a case, there must be an actual dispute involved.

For example, if someone wants to sue their neighbor for playing loud music at night, they can only do so if they have actually been affected by the noise. If they have not been affected, then there is no actual dispute, and the case cannot be heard in federal court.

This requirement is important because it ensures that federal courts only hear cases that have a real impact on people's lives. It prevents people from using the court system to ask hypothetical questions or to seek advisory opinions.