A father and son in the city of Zama, Japan, during its annual sunflower festivalToru Yamanaka / Getty

Earlier this month, the 38-year-old Japanese environment minister, Shinjiro Koizumi, did something that would not make national, or even local, news in many industrialized countries: A couple of days before the birth of his and his wife’s first child, he said he planned to take time off from work to care for the baby.

Koizumi’s planned leave is meager—he expects to take about two weeks off over the course of three months, and might still work part-time or remotely during those two weeks. But his decision was unusual for a Japanese father, let alone a prominent national politician (and the son of a former prime minister).

The hype around Koizumi’s minimal leave reflects the disconnect between his country’s official parental-leave allowances and how things work in practice: Japan offers one of the most generous paternity-leave packages in the world (a full year), yet the rate at which eligible fathers working in the private sector take leave is quite low (about 6 percent).  

For a host of reasons, Japan’s government would like that rate to be much higher. Research indicates that dads who take leave are more involved as their kids grow up, which improves both the kids’ and the dads’ physical and mental health (and moms’ too, no doubt). And in Japan in particular, where low birth rates have led to a scarcity of workers, if more fathers took parental leave and picked up more child-care responsibilities, mothers might have an easier time entering, or staying in, the workforce (and, in the longer run, Japanese families might be encouraged to have more children).

What’s more, a 2017 Japanese government-commissioned study found that just over a third of new fathers wanted to take paternity leave, but didn’t. What’s stopping Japanese dads from taking time off?

Policy and cultural norms each play a role when it comes to who takes parental leave and how much, and in Japan, culture has been the more powerful force. According to Machiko Osawa, the director of the Research Institute for Women and Careers at Japan Women’s University, the country’s work culture strongly discourages dads from taking time away from the office. “Taking paternity leave is more likely to reduce promotion possibilities in the future, since this is a signal that a man values his private life,” she wrote to me in an email. “In Japan, those who put work as a priority and work long hours receive high evaluations and are more likely to be promoted.”

In the past several years, a small number of men who object to these customs have filed lawsuits against their employers for what they say is unfair treatment. One, a Japanese national in his late 30s who has preferred to stay anonymous, claims that his employer, the sportswear company Asics, punished him after his stints of parental leave following the births of his two children. He maintains he was moved from a sales-and-marketing position to a warehouse job, doing manual tasks; after he sustained a shoulder injury at work, he was assigned to a different desk job, one that he claims to have no expertise in. “I spend all day staring at my computer with not much to do,” the man told CNN. Asics denies his allegations, and said in a statement it “look[s] forward to clarifying the facts in court.”

A country’s work culture can limit the success of even generous policies. Japan’s exceptionally long parental leave and relatively high pay for participating fathers—the country gives dads making average earnings roughly 60 percent of their wages during a year-long leave—is of little use if dads fear negative repercussions at work for taking time off. In South Korea, which gives its fathers 53 weeks of leave, a demanding work culture also contributes to a low participation rate (as does the fact that dads taking time off there are only paid at most 30 percent of their earnings). “It’s not sufficient to have the leave if the culture doesn’t support it,” said Monika Queisser, the head of social policy at the OECD, a group representing 36 mostly wealthy countries.

Just as different governments vary in how much paternity leave they offer (or if they offer it at all—the U.S. and many other countries provide none), various countries’ fathers opt in at very different rates. Among the OECD’s member countries, the share of parental-leave takers who are men is as high as 40 percent or more in some Nordic countries and Portugal, and as low as 2 percent or less in the Czech Republic, Australia, and others.

Researchers have identified a handful of factors that affect these rates. First, Queisser told me, many programs pay workers only a percentage of their income during their time off; naturally, the higher the percentage, the more likely fathers are to take leave. Second, she said, they’re also more likely to take time off if a program offers paternity leave specifically, as opposed to leave that’s given jointly to couples to be divided up at their discretion. (In those cases, women are more likely to take leave than men, generally because of cultural norms and because men’s earnings tend to make up a larger portion of a household’s income.)

Iceland is one country that illustrates these correlations. Queisser told me that, starting in the early 2000s, the country made its paternity leave “more generous—they increased the days, they increased the payment rates—and you could see as this went on that more and more men were actually taking this leave.” In 2016, nearly 30 percent of parental-leave days taken in Iceland were taken by men—the highest male share among OECD countries.

While this strategy may not have worked in Japan thus far, the case of Germany demonstrates how changes in policy can nudge culture forward. In the mid-2000s, Germany started giving a “father bonus”—two additional months of leave for parents to divvy up—to households in which the father took at least two months off; this helped increase dads’ participation rate.

“I wouldn't say the Germans are comparable to Japan, but [they also have] large gender inequalities in the labor market, a very male-dominant earner model, and women stopping work or working only a few hours part-time once a child arrives,” Queisser said. “So the German policy has been very successful in [getting] fathers [to] take leave.”

It’s unclear where this interplay between policy and culture would leave America’s working fathers if the U.S. government were to start offering them paid leave. On one hand, Queisser said, “If American fathers would react like fathers elsewhere in the world to being offered leave with a generous income replacement, then you would expect them to use it a lot.” But on the other, she said, the precariousness of some Americans’ employment might limit participation: Workers without strong labor protections would probably hesitate to take leave if they thought that doing so might cost them their job, or hinder their prospects of a contract renewal. For now, in the absence of a universal government policy, these negotiations between rules and norms take place within the microcultures of individual American workplaces.

Changing policy, while not easy, is at least straightforward—it’s a matter of writing new laws. Changing culture, though, is a messier task, resistant to legislative decrees. That’s discouraging in the case of Japan’s work-first culture, but Queisser does see indications of changes to come around the world. “We can already see that younger generations place more importance on purpose and flexibility and work environment than just loyalty to the company and income and career progression," she said. As more people in those younger generations become parents—Shinjiro Koizumi among them—perhaps they will be the ones to push cultures toward equality.

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