With guns drawn, the police officers broke down the door of the suburban Phoenix home in the early hours of a February morning. “Come out with your hands up!” an officer yelled, with the dark front porch and foyer inside suddenly flooded with light from the officers’ flashlights.

The target of the raid: an unvaccinated 2-year-old boy with a high fever.

Video from the officers’ body cameras that was released Thursday shows that moments later, the child’s father emerges, walking out backward with his hands over his head. The boy’s mother then comes out, too, cradling her young son in her arms.

The boy was whisked away to a hospital, and since that raid on Feb. 25, he and the couple’s two other children, ages 4 and 6, have been in the state’s custody. The parents have been charged with child abuse.

The boy’s case is among the most extreme examples of the authorities overriding the rights of parents to make decisions for their children’s health, and it comes at a time of rising concern about unvaccinated children infecting others around them.

The parents, Brooks Bryce and Sarah Beck, say the authorities drastically overreacted. “They treated us like criminals, busting in our door,” Bryce told a local TV station. “I mean, I don’t know what kind of trauma that did to my kids.”

But the Chandler Police Department has defended its role in the confrontation, saying it was compelled to carry out a court-ordered welfare check after the child’s doctor became concerned that the boy might have meningitis, a potentially life-threatening illness, and was not receiving necessary emergency care.

In rare cases, parents can be stripped of their ability to make health care decisions on behalf of their children. Even rarer are the occasions when parents lose custody of their children for declining treatment.

But with 315 individual cases of measles confirmed in 15 states this year, authorities are on high alert for people exhibiting symptoms of infectious diseases, especially children and toddlers who lack vaccinations for that disease and other illnesses.

Under Arizona law, parents may decline vaccinations for their child based on personal, religious or medical exemptions. But that law is in opposition to the “parens patriae” theory, a centuries-old principle that empowers the state to look after the interests of children and others unable to care for themselves.

“It’s a pretty high standard to meet,” said Douglas S. Diekema, who has been a practicing emergency room doctor for 30 years at Seattle Children’s Hospital. “I don’t know that I’ve ever called Child Protective Services, though I’ve thought about it a couple of times.”

Police records show that on Feb. 25, Beck had taken her 2-year-old boy to a clinic, where his temperature was recorded at above 100 degrees.

The child’s doctor became concerned that he could have meningitis, after learning that he was lethargic and had not been vaccinated. Beck was told to take him to an emergency room.

“I called the doctor back and said, ‘Hey, I’m not sure how you got this 105 reading, my son’s acting fine,’” Beck told a local TV station. “‘This doesn’t really seem like a medical emergency.’”

The child’s doctor, after learning that Beck had ignored the recommendation to take the child to the hospital and having follow-up phone calls to the family go unanswered, then contacted the Arizona Department of Child Safety.

Asked to do a welfare check, police officers arrived at the family’s door, but were not allowed in. The body camera footage released Thursday shows the police twice knocking and trying to enter, before an officer reaches Bryce by telephone just before midnight, and tells him that he needs to verify that their youngest child is improving.

“No, you don’t need to,” Bryce replies. He remains polite, saying “No, thank you” when he’s asked to come out of his home.

An emergency court order was issued, allowing police to take the child into custody. The officers asked the family to leave their home and take the child to the hospital, the video shows. After two more unsuccessful attempts at knocking at the door, they reminded Bryce that they had a court order and broke down the door.

Though neither parent was arrested, each was charged with one count of child abuse after an investigation. Two of the children, including the youngest, were taken by ambulance to the hospital, and the third was taken by the Department of Child Safety, according to the police.

All three children remain in separate foster care placements, according to The Arizona Republic. Diekema, the emergency room doctor in Seattle, said he personally encounters parents refusing a treatment plan “maybe every month or two,” meaning it likely happens in his hospital on a weekly basis. But there are procedures in place to stave off a hospital visit escalating into a child custody battle.

Sometimes, he said, a compromise can be found on a less aggressive form of treatment that is acceptable to the doctor; other times, another doctor at the hospital can give a second opinion, which some parents find more comforting.

Diekema, who is also a bioethics professor at the University of Washington School of Medicine, said that he tries to avoid coercion when he can. He recalled telling a patient’s parents, “I hate to say this, but I have to let you know that if you walk out of this emergency department, without agreeing to something that makes me comfortable, I’ll have to call child protective services.”

He said the doctor in Arizona would have been obligated to call the authorities if the family did not follow the clinic’s instructions.

The boy was eventually found to have a respiratory illness. A judge has told the child’s parents that the state wants them to regain custody of their children, but it was unclear when that would happen.

“We love our children, we love them,” Beck told another local TV station. “If our children needed help, we would absolutely help them.”