Lemon test

The Lemon test came from Lemon v. Kurtzman (1971), a case about state aid to religious schools. It asked whether a law had a secular purpose, whether its primary effect advanced or inhibited religion, and whether it excessively entangled government with religion. A law failing any prong violated the Establishment Clause.

Later justices added refinements, such as an "endorsement" test asking whether a reasonable observer would see government as endorsing religion. Over the years several justices criticized Lemon as unpredictable. Some religious displays and practices, including legislative prayer, were upheld without applying it, and Justice Antonin Scalia compared it to a ghoul that kept coming back from the grave.

In Kennedy v. Bremerton School District (2022), the Supreme Court stated that it had long ago abandoned Lemon and that Establishment Clause claims must be judged by reference to historical practices and understandings. That approach resembles the history and tradition test used in Second Amendment cases. Supporters say it gives religious expression more room in public life and rests on text; critics, including defenders of separation of church and state, say it leaves unclear how courts will decide cases and may weaken protections for religious minorities.