Just months after dismissing a similar request from a Georgia congressional candidate, the Supreme Court has again shot down anti-vaccine activist Robert F. Kennedy Jr.’s attempt to put a misleading ballot measure on the California primary ballot. In a brief order, the justices rejected Kennedy’s plea to overturn lower court rulings against his proposal. The initiative sought to repeal a state law that requires children to be vaccinated before attending school, a measure overwhelmingly supported by public health experts.