Constitutional Law
Establishment Clause
Definition
The Establishment Clause of the First Amendment prohibits the government from establishing an official religion, preferring one religion over another, or preferring religion over non-religion. The Lemon test historically required that a law have a secular purpose, a primary effect that neither advances nor inhibits religion, and avoid excessive government entanglement with religion. More recently, the Court has emphasized historical practices and traditions as the framework for evaluating Establishment Clause claims.
Example
A public school displays the Ten Commandments in every classroom. This may violate the Establishment Clause unless it has a secular educational purpose.