I agree, but it is a "religious based law" because it's rooted in a "holy book," the same way Mosaic Law is rooted in an ancient "holy text."
I understand your point, but I don't think we need to defend Sharia Law, we just need to point out to all who hear the fear mongering that no one in this country needs to fear Muslim America trying to implement Sharia Law because the US Constitution forbids it. To implement Sharia Law is to establish a religion in this country, and the Constitution is clear on the matter: "Congress shall make no law respecting an establishment of religion........."