JERSEY CITY — Every city in America knows that it’s a bad idea to prosecute low-level, nonviolent marijuana offenses. It wastes scarce municipal resources and does nothing to enhance public safety. What’s more, even though whites and blacks use marijuana at similar rates, blacks are more harshly punished for it.

That’s why, on July 19, marijuana offenses were effectively decriminalized in Jersey City, New Jersey’s second most populous city.

Prosecutors treated every marijuana case that day as a violation instead of a misdemeanor, unless driving under the influence was involved. We told our prosecutors to ask for no more than a $50 fine, or just five hours of community service if the defendant couldn’t pay that fee. Instances like the absence of any public nuisance or a low likelihood of re-offense would warrant outright dismissal. We also stressed the importance of diverting people with an obvious drug addiction toward social services.

The goal of the policy was to avoid the collateral consequences of a conviction. Our assistant prosecutors approved. It meant less time subpoenaing police officers for marijuana prosecutions that had zero impact on public safety, and more time preparing for more consequential prosecutions of assault, theft and domestic violence.