Nebraska is considering such an act, and one of our Touchstone families in Lincoln, Nebraska, have written an op-ed about it posted here on the website of the Omaha World-Herald, in which they include quotations on conscience from Founding Fathers:

Our nation has long upheld the protection of individual conscience from governmental coercion. Thomas Jefferson wrote, “Our rulers can have authority over such natural rights only as we have submitted to them. The right of conscience we never submitted, we could not submit.”

In a letter to the Quakers, George Washington asserted that government was instituted, among other purposes, “to protect the persons and consciences of men from oppression.”
How far we’ve come. The state will always oppress unless held in check by other forces. When it gains leverage over those forces–whether those such as the press, the family, the church–it’s only a matter of time. You will no longer be free to teach you own children right from wrong. It happened in Russia, it happened in Germany, it has happened wherever there have been reigns of terror sponsored by the state and re-education camps, work camps, gulags. Why is that not obvious? “Can’t happen here,” is a way of saying, “We’re not like other human beings.” The camps might be much more comfortable, but they’d still be camps. And force comes in many forms, including not being able to find work because one’s views are not acceptable.