IN MAY, MINNESOTA REACHED AN UNFORTUNATE MILESTONE: The state had seen more measles cases in the first five months of 2017 than the entire country had experienced in all of 2016. The number of cases was, at recent count, 79. Most of those diagnosed with measles have been children, and more than a quarter of them have required hospitalization. While no one has died during the outbreak, some children may face long-term complications that include neurological damage and a greater susceptibility to future diseases.

The outbreak can be traced to parents who don’t wish to vaccinate their children—perhaps from religious beliefs or the idea, based on now-disproven science, that vaccines may give their child autism. When a parent does not want to vaccinate a child, a pediatrician has few good options. The physician can educate or cajole the parents or refuse to take on the child’s care. But as frustration with “anti-vax” parenting grows, some pediatricians want to go one step further if all other attempts to induce compliance fail: calling child protective services to report the maltreatment of a child.

These physicians consider a refusal to vaccinate to be a case of clear-cut medical neglect—an offense in which a parent refuses proper medical care to the point of putting a child in serious danger. “Parents have a responsibility to get their child vaccinated,” says Frank A. Chervenak, an obstetrician and gynecologist at Weill Cornell Medicine and New York-Presbyterian. “It’s very straightforward.” In an article in The Journal of Pediatrics in February 2016, Chervenak wrote that “informed refusal becomes child neglect, because [parents] are refusing to authorize evidence-based, effective and safe preventive care.”

Whether refusing a vaccine qualifies as neglect, however, is a topic of debate. “If the risk doesn’t look immediate, it’s probably not neglect,” says Dorit Reiss, a professor at University of California Hastings College of Law in San Francisco, who studies legal issues related to vaccines. The diseases for which kids receive vaccines are now so uncommon, she says, that refusing usually doesn’t put the child in immediate danger. “And most states have exemption laws, allowing parents to sidestep vaccination on grounds of personal belief,” Reiss adds. “That complicates the argument further.”

Doug Opel, a pediatrician and associate professor at the University of Washington School of Medicine, collaborated with attorney Efthimios Parasidis, associate professor of Law and Public Health at the Moritz College of Law at the Ohio State University in Columbus, to consider the legal precedents. They found only nine cases in which a parent was brought before a judge on grounds of medical neglect because of vaccine refusal.

In seven of the nine cases, vaccine refusal was considered medical neglect by the court—but five of those cases were in states that did not allow religious or philosophical exemptions to vaccination at the time. In states that did allow those exceptions, the legal arguments focused primarily on whether a religious claim was valid, rather than on the medical risk to a child, says Parasidis. Opel and Parasidis published these findings last December in the American Journal of Public Health.

Beyond the question of whether vaccine refusal constitutes neglect is another issue: What should happen if child protective services is called in? Weill Cornell Medicine’s Chervenak doesn’t want CPS to remove the child from the home, though he does think parents who refuse to vaccinate should be flagged by the agency. “The purpose of contacting CPS is to help persuade the parents to authorize vaccination,” he says. “It’s a way to communicate the importance of fulfilling their parental responsibility.”

Current policy recommendations from the American Academy of Pediatrics, meanwhile, direct pediatricians to call protective services only when vaccine refusal represents an immediate danger—refusing a tetanus shot after a deep, contaminated wound, for instance. In line with the AAP recommendations, Opel says that he prefers communication over punishment when approaching parents about vaccination. “We need to be very cautious with involving CPS for vaccine refusal,” he says. “It will likely be perceived as coercive and undermine the doctor-parent relationship. My preference is to work with parents, build rapport and trust, and keep communication lines open.”

Representatives from child welfare agencies in Texas, California and Michigan have said that they would not have the authority to investigate a family for medical neglect purely on the grounds of vaccine refusal. But policies in most states are not formalized, and Opel says that CPS needs to provide more guidance for pediatricians.

The problem is that when pediatricians face a parent who consistently refuses vaccines, “they don’t have many communication tools in their toolbox,” says Opel. “This is a frustrating scenario.” With more clarity about CPS guidelines, medical agencies and practitioners will be better able to reach the shared goal of protecting children.