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Besides, closing some parks may well cause what outdoor access remains to become even more crowded—people have already been reporting crowding elsewhere as a response to park closures. All this may avoid the pictures from parks that get people upset and encourage scolding, but it does not make us safer. Instead, our focus should be on restricting access to truly high-risk areas (such as playgrounds) while keeping open trails and lawns in a manner that is compatible with social-distancing requirements.

Young people are a particular challenge for any park and outdoor policies. It’s tempting to close a park because people are congregating there! In large groups! (As the tweet announcing the closure of Brockwell Park loudly proclaimed.) Preventing in-person social activity, though, especially among young people, is a matter of persuasion. Research into the effectiveness of abstinence-only education is instructive on this point: abstinence-only education is positively correlated with higher rates of teen pregnancy, even after controlling for factors such as socioeconomic status. Persuading teenagers to completely avoid sexual activity is quite difficult, and pretending we convinced them through instruction can just drive the behavior underground without safe-sex and birth-control practices.

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A similar difficulty exists for youth socialization during a pandemic. Young people have repeatedly heard that the coronavirus disproportionately affects the elderly. And also, they’re young: Their own mortality rarely works as an argument to stop them from doing something. We would do better to appeal to their altruism, by explaining that they could spread the virus to vulnerable people, but doing so requires maintaining legitimacy. Keeping parks open could even be seen as a form of harm reduction for congregating youth. If a group of 10 young people goes to a park like Brockwell and is kept six feet away from every other group, the police shooing them away may end up being pandemic theater that might increase the risk of transmission among the group members if they instead spend that time socializing anyway in a cramped, poorly ventilated apartment. Parks could even put a limit on how many people can be together at once, which again would bring about harm reduction compared with an out-of-sight but larger gathering indoors. Meanwhile, we should keep trying to persuade the youth to socially-isolate but let’s also not kid ourselves that we have been completely successful if we merely manage to improve the optics by closing access to parks.

The history of disaster response is full of examples of extraordinary goodwill and compliance among ordinary people that disintegrate after authorities come down with heavy-handed measures that treat the public as an enemy. Rebecca Solnit’s book A Paradise Built in Hell details many such cases, such as the lives lost when the military was ordered into post-earthquake San Francisco in 1906 to control the dangerous and unruly “unlicked mob” that was primarily a figment of the authorities’ imagination. Unfortunately, the official response worsened the subsequent fire (which was more damaging than the earthquake itself) by keeping away volunteers “who might have supplied the power to fight the fire by hand.” Some ordinary citizens were even shot by soldiers on the lookout for these alleged mobs of looters and dangerous behavior from citizens. Similarly, in the aftermath of Hurricane Katrina, as a review of Solnit’s book summarized, “there were myriad accounts of paramedics being kept from delivering necessary medical care in various parts of the city because of false reports of violence.”