US conservative Christians and science advocates are clashing again, this time in Tennessee over a bill that would allow debate in public schools over theories like evolution.
Lawmakers from the southeastern US state home to a strong base of ultraconservative "Tea Party" activists have approved the bill, which now awaits the signature of Governor Bill Haslam, a Republican.
The measure, which could pass by a Tuesday deadline, would allow public schoolteachers to challenge accepted science on topics such as climate change and evolution in their classrooms without facing sanctions.
If it passes, Tennessee would join nine other states with similar laws promoting creationism, more or less explicitly.
Critics have labeled the legislation the "Monkey Bill" in reference to the highly publicized 1925 "Scopes Monkey Trial" in which Tennessee charged high school science teacher John Scopes of violating a state law against teaching "that man has descended from a lower order of animals."
The Tennessee Science Teachers Association and the state chapter of the American Civil Liberties Union rights group, the measure's biggest critics, are calling for Haslam to veto it. They say it would provide legal cover for educators to teach pseudoscientific ideas.
"They are not talking that much about creationism but rather about Intelligent Design," said Hedy Weinberg, executive director of the ACLU's Tennessee branch.
"It's a very nuanced and clever way... to challenge the theory of evolution and allow teachers to inject Intelligent Design and neo-creationism." Intelligent Design is the idea that scientific evidence can show that life forms developed under the direction of a higher intelligence.
The measure states that "teachers shall be permitted to help students understand, analyze, critique and review in an objective manner the scientific strengths and scientific weaknesses of existing scientific theories covered in the course being taught."
It also says the legislation "shall not be construed to promote any religious or non-religious doctrine."
In a letter to lawmakers, the Tennessee members of the National Academy of Sciences argued that the bill would "miseducate students, harm the state's national reputation and weaken its efforts to compete in a science-driven global economy."
The Tennessee Education Association, meanwhile, blasted the "unnecessary legislation."
But Haslam has already indicated he would "probably" sign the measure into law.
The Discovery Institute, whose model legislation inspired the bill, hailed the passage of a text that "promotes good science education by protecting the academic freedom of science teachers to fully and objectively discuss controversial scientific topics, like evolution."
Based in Seattle, Washington, the group backs the teaching of alternatives to evolution in public schools and supports research into Intelligent Design, a form of creationism.
The creationist offensive is part of a long-running battle, in a country where only a quarter of the population believes whole-heartedly in evolution, between advocates of non-religious teachings in public schools and conservative Christians who say man is a divine creature not descended from apes.
It was not before 1968 that the US Supreme Court ruled it was unconstitutional, based on the separation of church and state, to teach anti-evolution principles.
And in 1987, the high court said that mandatory teaching of creationism was against the Constitution because any such law intended to advance a particular religion.
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