A Kentucky school district's decision to remove the Ten Commandments from its buildings after it was pressured to do so by an atheist organization this week is the latest in a decades-long fight over their display on government property.

In another recent case, the Tennessee legislature passed a bill unanimously allowing for the Ten Commandments to be posted in the state's public buildings.

State public school systems have been a key battleground in a struggle that continues to rage nationwide.

The Ten Commandments are the biblical laws.

As well as playing a fundamental role in Christianity, they are central to  Judaism and Islam.

Breathitt County removed the Ten Commandments after receiving a letter from the Freedom from Religion Foundation (FRFF).

The letter complained that their display violated the U.S. Constitution and called for their removal.

The FRFF letter was prompted by a complaint received from a Breathitt County student.

Kentucky's Board of Education issued a statement agreeing with the decision made by the school administration.

The statement said that the display of the Ten Commandments in Breathitt County schools "violated the U.S. Constitution's prohibition on the establishment or endorsement of religion by a public agency."

The statement referred to the Establishment Clause from the First Amendment of the U.S. Constitution.

Together with a clause called the Free Exercise Clause, the First Amendment states:

"Congress shall make no law respecting an establishment of religion, or probiting the free exercise thereof."

The U.S. Supreme Court's interpretation of what in its entirety is called the Religious Clause has evolved over time.

In the 1940s the U.S. Supreme Court applied the Establishment Clause to the States, not just to Congress, in conjunction with interpreting the Fourteenth Amendment. The Fourteenth Amendment was passed after the Civil War.

It granted the rights of the First Amendment to former slaves and recognized Americans as both citizens of the United States and their State.

In 1971 the Supreme Court developed the Lemon Test to help determine if a governmental action violates the Establishment Clause. This test indicates three aspects:

* The government's action must have a secular legislative purpose;

* The government's action must not have the primary effect of either advancing or inhibiting religion.

* The government's action must not result in "an excessive government entanglement" with religion.

The Supreme Court has used the test since, including in making decisions on cases involving the display of the Ten Commandments in Kentucky in 1980 and 2005.

Legal advocates for allowing the display of the Ten Commandments on public property believe the Supreme Court's rulings related to the Establishment Clause have been flawed.

William Saunders of the Family Research Council (FRC) stated in a publication in 2005 that the Supreme Court has refined the Lemon test to the point that a governmental action cannot even convey the impression that it is endorsing a religion.

Saunders also indicated that the current test to determine if the Establishment Clause has been violated does not match the intent of the authors who the First Amendment.

It would be better, he said, to have a "coercion test" which would match the intent of the Founding Fathers of the United States.

"The questions the courts should ask, is whether the challenged governmental action privileges one religion or one denomination over others, and then compels those of different beliefs to conform to the dictates of the privilege religion or denomination."

The Liberty Counsel, like the FRC, has fought in the courts to maintain the right to display the Ten Commandments on public grounds.

It recently won a case in which the American Civil Liberties Union (ACLU) sued the school board in Giles County, Virginia for posting the Ten Commandments along with other foundational documents on law and government.

In 2002 the Liberty Counsel published an article arguing that the Supreme Court had misapplied the Establishment Clause and in effect created new law prohibiting the free exercise of religion.