The Supreme Court just gave anti-vaccine parents an alarming win.

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The Supreme Court handed religious anti-vaxers a significant victory on Monday, setting aside a lower court decision that upheld New York’s school vaccine mandate despite its lack of a religious exemption. In a brief, cryptic order, the justices told the lower court to reconsider the case in light of their 6–3 ruling last term in Mahmoud v. Taylor . That decision expanded parents’ ability to demand an exemption from any school policy that “substantially interferes with the religious development of their children.” By extending Mahmoud to immunization requirements, the court revealed that some justices—perhaps a majority—are preparing to give parents a First A