Hisham Breedlove sings at the Federal Triangle Metro station for tips on July 19 in Washington. (Matt McClain/The Washington Post)

Singer Hisham Breedlove has a precise routine for staking out a performance spot inside Metro stations.

The operatic countertenor places his belongings on the station mezzanine. Then, he nods a hello to the station manager, takes a deep breath and begins to belt out the first notes of a popular aria — while silently praying that no one complains.

“Just one person has to go to him and say, ‘You know what, that guy is singing there, I don’t like it,’ and then by law the station manager has to tell me to leave,” said Breedlove, who has been singing in Metro stations for years. “That’s just how it is.”

Breedlove is one of the region’s longtime subway buskers — a purveyor of performance art in public spaces that many commuters have come to view as an indelible, and invaluable, part of life in a bustling city.

But for the musicians who earn their livelihoods playing music in or around subway stations, things have never been harder. Lawsuits have helped to codify rules and strictures on when and where they are allowed to perform. The fight for prime performance locations — like the sidewalk outside the entrances to the Gallery Place station — has become contentious as buskers using boomboxes and amplifiers square off against rankled residents and concerned lawmakers.

Even the spot where world-class violinist Joshua Bell famously played his 43-minute “Pearls Before Breakfast” performance — the breezeway at the top of an escalator emerging from L’Enfant Plaza station — is now a place where security guards routinely order buskers to move along.

The increasingly complex geographic challenges for subway musicians is just one of many reasons their jobs are becoming harder and more unpredictable.

“You have a lot of [police] officers who will make up their own rules about where you can and can’t be,” said musician Mark Francis Nickens, who has been busking in and around Metro stations since 1987. “So you’ve got to know the laws. And I try to be nice about it, but I stick up for myself.”

Breedlove embraces a Metro rider at the Federal Triangle station. (Matt McClain/The Washington Post)

But that rule is interpreted, and enforced, in a lot of different ways.

Nickens considers anywhere outside the fare gates fair game. Breedlove says he uses Metro’s signature hexagon-shaped tiles to judge where he should and shouldn’t be standing. He does venture into the underground level of the station — as he did on a recent Thursday, belting out “Ave Maria” to passersby — but he knows that his presence is only allowed at the discretion of station managers.

He recalled one rider who frequently passed by him at the Court House station.

“This one lady just could not, for the life of her, stand me!” Breedlove said.

She made her displeasure known to the station manager, who informed Breedlove: “Sorry, if she doesn’t like you here, you can’t be here.”

Breedlove said he’d leave, but he kept returning.

“I was trying to kill her with kindness,” he said. “But even after several months of smiling at her every day — nothing, nothing was budging.”

She kept complaining to the station manager. Finally, Breedlove gave up and abandoned Court House as a busking spot.

Buskers say different transit police officers and station managers have different interpretations of the rules. That’s led to more competition for the performance spots where buskers know they’re welcome, Breedlove said. It also means a sometimes fractious relationship with Metro Transit Police.

When Metro first opened in 1976, musical performances on any Metro property were strictly forbidden. Local leaders were trying to create a contrast to the dingy, cacophonous New York subway by creating spaces with grandiose arcing ceilings and an aural aesthetic of serenity.

But musicians, and others, bristled. In the late 1980s, Metro changed its rules, allowing for noncommercial “free speech activity” as long as individuals were aboveground, off the platform and more than 15 feet away from fare gates or escalators.

Breedlove stretches between songs as he sings at the Federal Triangle Metro station. (Matt McClain/The Washington Post)

Then, in 2014, an acoustic guitarist named Alex Young grew tired of getting hassled by transit police at the Vienna, West Falls Church and Ballston stations. So he sued Metro and a U.S. District Court judge upheld his right to perform and solicit tips, determining that subway busking was a form of free speech, not panhandling or commerce, and therefore a protected practice on the outskirts of each Metro station.

Recently, however, there’s been a crackdown on what constitutes the outskirts. And concerns about noise at Gallery Place prompted hearings by the D.C. Council. (So far, the council has declined to enact an emergency ordinance.)

And the interior of stations, particularly the platforms, remain no-go zones for busking musicians, even though performers are commonplace on subway platforms in Boston and New York.

Metro General Manager Paul J. Wiedefeld has advocated for broadcasting recorded music in stations and, at his request, smooth jazz, mellow music and occasional holiday tunes are played on the speaker system in some downtown stations.

But Wiedefeld said recently that he’s not considering allowing musicians to perform on station platforms.

Then there are the ubiquitous cellphones, which have begun to diminish the serendipity of passing a guitarist playing a beloved ballad.

“It’s not appreciated or as revered now as much as it once was,” Nickens said of his performances, “because all you have to do is pull up your smartphone and Google any song you want, by any artist you want, and you can listen to it instantly.”

But they keep going, living for the moments when a passerby approaches and offers an edifying comment:

Some of the tips Breedlove earned for singing at the Federal Triangle Metro station on July 19. (Matt McClain/The Washington Post)

I heard your music, and it filled me with joy — it convinced me to keep on living, another told Nickens.

Those interactions are what is so special about preserving public space for buskers, said John Whitehead, a constitutional lawyer and president of the Charlottesville-based Rurtherford Institute.

Whitehead represented guitarist Alex Young in the 2014 lawsuit against Metro. And even now, he says, he gets occasional inquiries from people in D.C. or other urban centers in the country, who have been stopped by police from busking in public spaces or at transit stations. Whitehead tries to help them by providing case law supporting the idea that musical performances — even when they involve soliciting tips — are a form of protected public speech.

“I like to be encouraging to them,” Whitehead said. “I’d like to see more people out in the gallery of life . . . not just sitting inside all the time doing nothing. We should be celebrating people who want to be out in public squares, making their voices heard.”