The murders of 13-year-old Natsumi Hirata and 12-year-old Ryoto Hoshino in Osaka last month sparked a heated conversation in the media about the state of parenting in Japan.

Hirata and Hoshino were caught wandering the streets on security cameras during the wee hours of Aug. 13 before they were presumably picked up and killed. Neither child was homeless, and the question became: What were they doing out so late? In interviews, Hirata’s classmates said that she often went out at night and hung around on the streets, sometimes not returning home for several days.

What made the story incomprehensible to most reporters is that Hirata wasn’t considered furyō (delinquent) or even a runaway. Her wandering ways had less to do with typical adolescent rebelliousness than with the fact that she could go out, which means her death was implicitly tied to a lack of adult supervision. She didn’t seem to be the product of a broken home, though it’s been pointed out that her father is unemployed and her mother works late every day to provide for the family. Some media suggested that the parents often fought and that maybe the girl wanted to escape such an atmosphere, but there appears to be something else, a parent-child dynamic that doesn’t fit the usual complaints about permissiveness.

In its Aug. 31 issue, Aera wrestled with the implications but also pointed out that the problem of wandering kids is by no means a widespread phenomenon. The majority of minors are home by a reasonable hour and do not roam back alleys at night, though the number who do is increasing.

Except for Nagano, every prefecture in Japan has a regulation that prohibits children from being out at night without good reason. The National Police Agency has reported that in 2014, 429,000 children were confronted in public by police officers nationwide and brought back to police stations. Not all of these cases took place at night, but most probably did. A good portion may have been potential runaways, but such distinctions become blurry when parents don’t report their children as missing. At the same time, 1,210 adults were actually arrested for taking their children out after midnight, almost four times the number arrested for the same charge 10 years earlier.

The term that experts have adopted for such a dynamic is “flat,” since the relationship between parent and child is not vertical but horizontal. According to an expert on criminal psychology interviewed in Aera, though some people have characterized these relations as being akin to a “friendship,” there is very little warmth involved. The children don’t regard their parents with fear or respect for the simple reason that they don’t see much of them and haven’t developed any opinion one way or the other. The parent may eschew discipline out of either a fear of alienating the child or laziness, but in any case the children feel no “guilt” about staying out late and, regardless of their parents’ feelings about this tendency, they in effect are unable to stop the children from going out.

But another reason for the increase in wandering children is a change in the social atmosphere. In a recent feature, the Asahi Shimbun talked to Osamu Mizutani, a former public school teacher who himself walks the streets at night talking to young people he meets. He cites the rapid spread of convenience stores since the late 1980s, which provide wayward kids with rendezvous points with clean toilets and snacks. Two decades ago, they would assemble in the dark behind a convenience store, away from adult eyes. But now they hang around in front because they know “no one will challenge them.” Mizutani reckons that had even one adult confronted Hirata and Hoshino during their midnight ramblings, maybe the tragedy wouldn’t have happened. “Society has become uninterested in children,” he said.

In a report on NHK’s news show “Close-up Gendai,” smart phones were also cited as contributing to the increase in wandering children. The social networking app Line has made it possible for kids to create virtual communities that don’t require face-to-face contact, and so they have no sense of danger when they meet strangers.

As one policeman told NHK, parents buy smart phones for their children expressly so that they can keep track of them. Both parents and children think that if something happens to the latter they can call for help, but that doesn’t always happen, and certainly wasn’t the case with Hirata and Hoshino. A well-known children’s advocate, Kazuki Arai, says he uses Line to monitor the actions of wayward adolescents, and has found that they are subjected to violence even more than people think, but that they don’t tell anyone except their friends online. Some teen girls even text about being raped.

And this is something that the media, despite its natural tendency to emphasize the sordid details of tragic stories, hasn’t stressed enough. The man who was arrested for the murders of Hirata and Hoshino has already spent time in prison for abducting children, but even if parents do warn their kids not to talk to strangers, there seems to be little discussion of what might actually happen if they do, and thus the peril isn’t communicated effectively. Pederasty isn’t a subject deemed fit for public discussion, and as long as kids aren’t made aware of what some people are capable of, they may not be sufficiently cautious.

But without a stronger disciplinary will on the part of parents, even this scare tactic could backfire. If kids walking around at night are confronted by adults who try to get them to go home and who are then accused of being potential molesters, it’s going to be more difficult to get adults to act. Arai says that he knows of people who have tried to talk to young people on the street and the young people threatened to call the police on them. But if that happens, by all means call their bluff, because in the end, getting the police involved is exactly what you want.