SIGN UP FOR OUR NEWSLETTER

On a recent, unseasonably warm Saturday afternoon, the corner of Varick and West Houston streets is mostly unremarkable: trucks and taxis speed by, pedestrians saunter. But in front of 201 Varick — a multipurpose federal building, replete with post office and prison — roughly a dozen people, mostly young and attractive, have gathered around a line of round concrete planters, filled-in with dirt and woodchips but no plants.

Reverend Billy, the anti-consumerist street preacher and Green Party mayoral candidate, stands out among the congregants, sporting his blond pompadour and boldly blue trademark-suit. Those gathered are mostly members of his choir, preparing for the first leg of the day’s mini-tour of immigrant detention centers. “We’ve been dreaming of this detention center tour ever since we heard about it,” Billy tells one of his choristers. He takes a megaphone and points it into the sky: “I’m here!” he shouts at the building, to those detained inside. (It is unclear whether they can hear him.) “You will be free! Very soon!” Cryptically, he adds, “you’re already free! You’re freeing us!”

Service announcements from the Number 1 train trickle up through the sidewalk grates as the singers gather around the planters in groups determined by vocal range: baritones by the door, altos a few feet down. Two security officers arrive before the singing begins and stand nervously by the doors. “We’ll be done in 20 minutes,” Billy tells them. “What you’re doing is fine,” one guard says.

In the eye of the building’s security cameras, the choir, now dressed in their green robes, begins its song, with lyrics by Savitri D., Billy’s wife. We dance the day you are free/The jailers wander off, and we find the key. As they sing, their voices drifting into the urban afternoon bustle, Billy resumes shouting into the megaphone. “Our local Guantanamos must close now,” he says. “This is the immigrant city. We take Lady Liberty’s message seriously.”

The choir continues. We know you are citizens too/Workin’ and lovin’ Americans. Billy moves off to the side; Juan, one of the officers for the private security firm that guards the building, has asked him to sign something, what Billy later said he believed to be an application to rally near a federal facility, though he wasn’t sure. “How many people do you have detained here?” Billy asks, as he signs obligingly. Juan doesn’t know. (The male-only facility has 250 beds.) As Billy finishes, a woman leans over to the guard. “He’s gonna be mayor,” she tells him. Juan laughs. “Who, him?”

Better than Haiti, But Still…

Immigration and Customs Enforcement — or, I.C.E. — a division of the Department of Homeland Security, oversees a network of prisons that detain and process undocumented immigrants. Twenty such domestic facilities exist, from New York to California, many of them in the south and southwest; there’s also one in Puerto Rico. I.C.E. runs seven of them, sometimes in cooperation with local counties. Private corporations run the rest, like the one on Varick Street. Many of these facilities were in operation prior to 9/11, then under the jurisdiction of Immigration and Naturalization Services. A larger network of 500 centers — incorporating county jails, federal detention centers and for-profit prisons — held roughly 500,000 undocumented, destined-for-deportation immigrants last year, according to the New York Times.

Some of the immigrants in these jails have been detained because their visas expired; others never had visas, and were picked up during workplace raids or traffic stops. Some are asylum seekers. Others have been convicted of crimes, from misdemeanors to murder, and face deportation. More than 88 percent of the cases ICE brings in front of immigration courts are deportation cases. Most of the detainees are Latinos, although other ethnic groups are represented as well.