On Cinco de Mayo, Mount Pleasant marked the 20th anniversary of the riots that erupted along its main commercial strip with speeches and music in Lamont Park. But the celebration carried an extra meaning: After more than a decade, the restrictions placed on restaurants after the riots had finally been scrapped, and the party could go on at Haydee’s late into the night.

Here’s the history in a nutshell. In the late 1990s and early 2000s, the Mount Pleasant Neighborhood Alliance signed “voluntary agreements” with seven restaurants along Mount Pleasant Street NW, banning live music and imposing a laundry list of other limitations. Haydee Vanegas and Alberto Ferrufino, the owner of Don Juan’s, signed agreements in 1997 and 1998, but they say they didn’t realize what they were getting into.

“I signed [a] voluntary agreement, and I didn’t really know no more music, no more birthdays, no more community events, no more happy hours,” says Vanegas, listing the stipulations attached to her liquor license. “I thought it was ‘Don’t sell to minors, keep the place clean.’”

They quickly learned, however; the agreements put a damper on the culture of live music that helped Mount Pleasant’s largely Salvadoran immigrant population feel at home in the 1980s. (It also put a damper on profits: Vanegas estimates that the loss of live music cost her some $2 million over the years, since many customers don’t get off work until late at night, and leave early if nobody’s performing).

In 2007, a group of neighborhood residents volunteered legal assistance to help the restaurants fight the restrictions, and signed their own voluntary agreements with Haydee’s, Don Juan’s, and Don Jaime’s. Before the Alcoholic Beverage Control Board, Hear Mount Pleasant argued that music wasn’t a disturbance, while the MPNA insisted the neighborhood’s residential character and high density of children made it unsuitable for late-night entertainment they feared would bring revelers (and their cars) from outside the area.

In 2008, the ABC Board allowed some music—but with restrictions. Don Juan’s, for example, was allowed karaoke and roaming mariachi bands; a trio that sat still for an evening wouldn’t be kosher. Don Juan’s, Haydee’s, and Don Jaime’s had to stop the music weeknights at 11 p.m. and 1 a.m. on the weekends.

Underneath it all, the fight wasn’t even about live music as much as it was about who controlled the restaurants. The MPNA was willing to relax some limitations, but didn’t want to let them go completely, fearing that Hear Mount Pleasant might ditch the more permissive agreements it had signed with the restaurants. “Their heart’s not behind it,” said the MPNA’s Sam Broeksmit.

This year, the ABC Board disagreed, junking the MPNA’s agreements for Haydee’s, Don Jaime’s, and Don Juan’s. Already, Haydee’s offers music almost every night until closing time, and not just mariachi—many of Vanegas’ Latino clients have moved north over the years, as the neighborhood got more expensive. Now, local bluegrass and jazz outfits are popular offerings. At a celebration of the ruling on April 26, Don Juan’s was overflowing with yuppie families and their strollers. Vanegas sat in the front row, smiling broadly.

Mount Pleasant might be the most extreme example of a small group taking advantage of the ABRA’s “rule of five” to force restrictions on restaurants. But voluntary agreements, a quirk of D.C.’s licensing process that grants immense power to people living near alcohol-serving establishments, are still a major cost for anyone trying to open bars in neighborhoods all over the city. If you’d rather not abide by the hours of entertainment such neighbors would like to impose, be prepared to shell out big money for a lawyer, or find another location—which would-be entrepreneurs often elect to do.

Just ask Aleks Duni, who owns Marx Café on Mount Pleasant Street and books DJ nights. He’s already spent thousands of dollars in legal fees to get what concessions he already has on his MPNA voluntary agreement, but doesn’t want to eat the expense of failing if he tried to get it thrown out altogether. In a better world, he wouldn’t have to.

“The entire issue is to take off a law from the ABRA that says five people from the neighborhood can close your place if they say it’s too much noise,” he says, exasperatedly. “If the majority of the neighborhood is saying that, it’s a different matter. But five people? No way!”