Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
The compelling state interest test is a test used by the US Federal Courts in due process and equal protection claims (all claims with Constitutional bases, actually) under the Fourteenth Amendment for state action and under the Fifth Amendment for federal action. It is part of the strict scrutiny analysis that a federal court will employ when either a suspect class is involved or a fundamental right. A government action or statute subject to strict scrutiny must satisfy a compelling state interest that is narrowly tailored to achieve that interest. The court will give the strictest scrutiny of the state or federal action when it impacts or targets a specially protected class (race, ethnicity) or when a fundamental and Constitutionally protected right is involved (Freedom of Speech, Right to Vote). The compelling state interest test is distinguishable from the rational basis test, which involves Fourteenth and Fifth Amendment claims that do not involve a suspect class and involve a liberty interest rather than a fundamental right.