The U.S. Supreme Court has ruled that church-run institutions and religious schools are exempt from civil rights claims from their employees, stating that the principle of church-state separation bars bias suits from teachers.

Citing the First Amendment, which includes a “ministerial exception” that protects churches and their schools from undue interference from the government and its courts, Chief Justice John G. Roberts Jr. said that the state cannot infringe on this religious freedom if it forces a church or its schools to accept or retain “an unwanted minister. … The church must be free to choose those who will guide it on its way,” writes David G. Savage at the Tribune Washington Bureau.

Academics recognize the weight of the ruling. Notre Dame law professor Rick Garnett described it as “one of the court’s most important church-state decisions in decades.”

It “protects religious liberty by forbidding governments from second-guessing religious communities’ decisions about who should be their teachers, leaders and ministers.”

There is some dispute over the definition of “ministers”, and the ruling has declared that this definition includes teachers.

But University of Virginia law professor Doug Laycock — who defended the school — said  the ruling applies only to teachers who have religious duties.

“Teachers of purely secular subjects will still be able to sue.

“I expect teachers with substantial religious responsibilities will be covered,” and thereby barred from suing over discrimination.

Criminal prosecutions against churches and religious schools will be unaffected, lawyers said.

This comes after the U.S. Supreme Court rejected an appeal against a ruling that prevents public school facilities being used for religious services outside of school hours.

The U.S. Supreme Court decided to uphold a ruling that prevents religious groups from using public schools facilities for worship services outside of normal school hours, upholding the state policy against religious worship at its schools.

The Supreme Court rejected an appeal by the Bronx Household of Faith, an evangelical Christian church, citing the need for church-state separation. The church wanted to use a local school for Sunday religious services, including singing of hymns, prayer and preaching from the Bible. But the appeals court ruled that allowing the event to take place would violate constitutional requirements.

Jordan Lorence, an attorney for the Bronx Household of Faith, said that the policy against religious worship amounted to “viewpoint discrimination” and the appeals court authorized “censorship of private religious speakers.”

“This court’s review is needed to resolve an issue of exceptional and recurring importance, namely whether the government may exclude religious worship services from a broadly open speech forum,” Lorence said.

In the past, the First Amendment was used to strike down state laws that gave aid to religious schools. However, in recent cases, the highest court in the country has ruled against government interference with religion, citing the “free exercise” clause.