FORBES MAGAZINE RECENTLY NAMED Washington as America’s “Coolest City” for 2014, which is, well, cool. But in many respects, the District remains a button-down kind of place — sometimes a little too button-down.

We could offer plenty of examples. Exhibit A might be Metro’s policy on musicians who might like to strum, fiddle, trill or even sing on its property.

It’s not just that the transit agency forbids them from playing inside Metro stations, or even within 15 feet of entrances — fare gates, stairs, escalators and so forth. Metro’s policy also forbids performers from accepting tips, even if they comply with the rules by playing their instruments beyond the 15-foot buffer zone outside stations.

That is so not cool.

A federal District Court judge in Washington, Beryl Howell, agreed. In a suit challenging Metro’s draconian rule, Judge Howell ruled that buskers — street musicians — who comply with the transit agency’s other regulations can now receive tips from passersby outside fare gates and escalators.

The suit was brought by Alex Young, a 27-year-old guitar player who was being hassled by Metro transit police for doing no more than what he called brightening people’s days by entertaining them — and leaving his guitar case open as a receptacle for tips.

Thanks to the judge’s preliminary injunctions, Mr. Young can now keep on performing, and also collecting tips, as long as he observes the 15-foot buffer in Metro’s above-ground “free areas.”

Metro now says it intends to go to trial on the case, which would be foolish.

The agency has a legitimate interest in maintaining unobstructed access to the entrances to its stations. Although some transit systems elsewhere allow musicians more or less free access inside subway stations (Paris comes to mind), it’s reasonable for Metro to insist they play only above-ground. After all, as anyone knows who tries to hear announcements from a platform, the acoustics in Metro stations are bad enough without having to try to decipher the words through music.

Mr. Young’s lawyers argued that playing music for tips is a protected activity under the First Amendment and that Metro was violating his rights by shooing him away from the “free areas” outside station entrances.

Other American transit systems would seem to agree. We surveyed several major ones — Chicago, Boston, San Francisco — and none has a policy forbidding tips for buskers. While most ban musicians from playing inside stations, and some require musicians to obtain permits, none maintains a policy quite as strict as Metro’s 15-foot cordon sanitaire outside fare gates. As for New York’s subway system, by far the nation’s biggest, it seems to manage despite a stance on musicians that amounts to anything goes.

To its credit, Metro initiated a program a few years ago, known as MetroPerforms!, that allows musicians who win auditions to perform in the summer outside select stations, most of them in the District. But until now, even they haven’t been allowed to accept tips.

Mellow out, Metro. No one’s hurt, and no transit operations are affected, by musicians playing above-ground outside stations. The lousy ones won’t make enough in tips to keep going back, and the good ones will add a little diversion to the daily grind of a Washington commute. Which would be cool.

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