In America, 43 of the 50 U.S. states confer some type of civil or criminal immunity on parents who injure their children by withholding medical care on religious grounds. If your child has diabetes or a severe infection, and you pray for her instead of giving her insulin or antibiotics, she’ll probably die, but you’re largely off the legal hook. But that immunity doesn’t apply if you injure your child by withholding medical care for nonreligious reasons; for that, you can be prosecuted for neglect, abuse, or even manslaughter. This privileging of religion is dangerous to children—and has killed many...