To address the problem in California, the state legislature passed a law in 2012 requiring parents seeking an exemption to first talk with a health care provider about the risks and benefits of vaccines.
[Related: Look Up Your School's Vaccination Rates Online]
Last week the state's health department released the form that parents must use to request an exemption. It includes a box for a health care provider to sign, showing that the conversation has taken place.
But the form also includes something else. Another box reads, "I am a member of a religion which prohibits me from seeking medical advice or treatment from authorized health care practitioners."
Parents who check that box don't need to talk to a health care provider. "Signature of a health care practitioner not required in Part A", the form says.
Where did the box come from? California Gov. Edmund G. Brown Jr. When he signed the bill into law, he directed the state's health department to include a "separate religious exemption" on the form.
"It was a surprise," says Catherine Flores Martin, executive director of the California Immunization Coalition, a state-funded advocacy and education group. She and other public health types have been puzzling over it ever since.
"I don't think [Brown] is anti-vaccine at all," Martin said, noting that both the governor and legislators were heavily lobbied by groups opposed to childhood vaccines. "He's very pro-science. I could not say what drove him to do this."
But Martin and others say this new religious group exemption could fatally weaken the law.
"It will give parents who want to get out of it an easy out," says Dorit Reiss, at University of California, Hastings College of the Law. That includes parents who in the past checked the exemption box just because it was easier than taking the kids in for shots. "I'm not sure it's good public policy to encourage people to lie."
Reiss sees another big problem with the new exemption — it's not part of the law. "With all due respect to the governor, he can't unilaterally change the law," she says.
That opens up the state to legal challenges from both pro- and anti-vaccine groups, Reiss tells Shots, including constitutional questions like whether it discriminates against people who want an exemption but aren't religious, or whether parents have a right to refuse medical treatment for their children.
And it's going to make it pretty darned hard for schools or state agencies to know if parents need to get the doctor signoff or not. The forms says they don't. But the law says they do.
"We're going to live with it and see if the exemption rates stay the same or go up," Martin says. "If they go up, then essentially the governor gutted the bill by writing that."