More than a dozen Central Area drug dealers voluntarily walked into an auditorium full of police and prosecutors Thursday night and were presented with an ultimatum: Stop selling dope or prepare for prison.

Confronted with photos, video clips and binders full of evidence gathered in a yearlong operation along Seattle’s 23rd Avenue corridor, from Madison to Jackson streets, the dealers were promised they wouldn’t be arrested, prosecuted or sent to jail for 20 months or more if they embraced the job training, educational opportunities and chemical-dependency treatment being offered them.

Should they break the bargain by selling drugs anywhere in King County, the dealers were told they’d feel the full force of the law.

“The community here cares about you but will no longer tolerate drug dealing in their neighborhoods,” said Interim Seattle Police Chief John Diaz. “This isn’t a joke, and it isn’t a threat.”

At a news conference at Seattle Police headquarters Friday morning, Diaz acknowledged “there’s a risk in doing this,” but said it’s time to try something different to eliminate street-level drug dealing in the city.

“We’ve done sweeps, we’ve done undercover buys and crackdowns and we’re still not getting a handle on drug dealing in our neighborhoods,” he said. “We’re trying to change the culture and the norms in the neighborhood.”

The Thursday night gathering at the Langston Hughes Performing Arts Center was an invitation-only event, where uniformed officers checked names at the door and a who’s who of Seattle’s criminal justice system sat alongside the dealers’ families, friends and fellow community members. For an hour, a parade of speakers took the stage to encourage the dealers to take the first-of-its-kind deal to ever be offered in the state. The “candidates,” as they are called, were told to listen without comment or question.

When the hour was up, everyone filed out except for the dealers and their “people of significance” — a parent, a friend, a spouse — who were asked to stay and ask questions of the neighborhood service providers who were there to help them change the trajectory of their lives.

“I’ve already bought drugs from you. These binders, these are the cases I’ve got on you,” Capt. Paul McDonagh, commander of the Seattle Police Department’s East Precinct, told the men and women seated before him. “We’re not playing. You have to stop today. … And if you don’t stop, we will stop you and you will go to prison.”

Police and prosecutors spoke of how tired they are of the vicious cycle of arrest, prosecution and incarceration. King County Prosecutor Dan Satterberg called it “an extraordinary day,” given that the gathered dealers were being offered “an opportunity no one else in the county has ever got.” Vince Lombardi, an assistant U.S. attorney, warned that even those who aren’t “kilo dealers” or drug-cartel members could find themselves facing federal charges and serving time in distant states if they didn’t change their ways.

An addict talked of her journey to recovery and those who were there to help, while a local pastor made a spiritual appeal, imploring the dealers to change their destinies and in so doing, help heal their community. A longtime home and business owner recalled the time a body was dumped on her sidewalk and later, when a young man was shot in her front yard.

“In the mid-80s, crack cocaine came in and the whole community went to hell, excuse my language,” said Jean Tinnea, who’s lived at the corner of 20th and Union Streets for more than 30 years. “You are part of our community and I really hope you’ll take these hands that are reaching out to you tonight and rejoin our community.”

The program is based on one first implemented in High Point, North Carolina in 2004 by police and New York City professor David Kennedy, a criminologist at the John Jay College of Criminal Justice. Five years later, the city has virtually no remaining public drug dealing and violent crime has fallen 20 percent citywide, according to the college’s Web site.

Kennedy, who visited Seattle in June, spent two days in private meetings with law-enforcement officials, city leaders and pastors and activists from Seattle’s black community. His model, which is being replicated in places like Milwaukee, Nashville, Chicago and Indianapolis, is being backed by the U.S. Department of Justice, which awards federal grants to train officials on how to establish programs in their own hometowns.

City Attorney Tom Carr and former Police Chief Gil Kerlikowske, now the country’s drug czar, applied for the federal grant last year.

Five representatives from Seattle spent months learning the ins-and-outs of the Kennedy model — called a Drug Market Initiative (DMI) — and how best to replicate it here. The team included McDonagh of the East Precinct, a deputy city attorney and a municipal court judge.

Last week, Diaz sent letters to 18 Central Area dealers that police had built evidence against, inviting them to what was dubbed a “community call-in.” Sixteen attended. One person didn’t show up and the other was previously arrested on an unrelated charge.

But none of the dealers invited to Thursday’s meeting has convictions for violent felonies or gun charges, nor are they affiliated with a street gang, said Carr.

“This is a unique opportunity and a one-time deal,” Carr told the gathering. “We built these cases not to use them. We’re willing to toss them away on one condition: That you just stop.”

Go back on the deal, Carr warned, “and I can prosecute you for stealing a candy bar and put you in jail for a year — and I will.”

While police are offering low-level dealers an alternative to lockup, detectives are still going after the Central Area’s mid- and high-level dealers and gang members, McDonagh, the East Precinct commander, said at today’s news conference.

“We’re still in the neighborhood,” he said. “We’re pursuing them and preventing them from plying their trade.”

Bob Hood, the director of the Public and Community Safety Division in Carr’s office and leader of Seattle’s five-member DMI team, said today the ultimate goal is to dismantle the Central Area drug market. Crime data will be analyzed and the community will be surveyed in the coming months to determine if the effort is successful.

“The overall impact over the next several months should be the elimination of this drug market,” Hood said. “There’s nothing soft about this approach and we’re willing to try what seems effective elsewhere.”