Otis D. Washington was defiant and uncooperative right up to the end.

As he stood before a Ramsey County district judge Thursday to learn his fate for preying on vulnerable girls and young women and selling them for sex — and sometimes forcing himself on them as part of his coercion — the 30-year-old St. Paul man showed little remorse. He asked for no forgiveness and accepted no responsibility for his crimes.

"Do what you all want to do," Washington told Judge Rosanne Nathanson.

With that, Nathanson slapped Washington with a 40-year prison sentence, the longest in Minnesota history for sex-trafficking convictions.

Washington, his brother and their two uncles were convicted last year for running a sex-trafficking ring that used physical, sexual and mental abuse to coerce girls and women, many of whom had mental health issues or came from troubled homes. One victim reported turning 20 tricks on some nights.

For authorities and victim advocates, Washington's sentence is vindication for the work they do and a warning to perpetrators that such crimes won't go unpunished.

"There's hope for the whole state, and I think there's hope for survivors," said Wendy Assal, women's program coordinator for the advocacy group Breaking Free.

A jury convicted Washington in November of soliciting someone under 18 to practice prostitution, soliciting an individual to practice prostitution, two counts of promoting prostitution of an individual and conspiracy to engage in sex-trafficking.

On Thursday, Nathanson handed down five consecutive sentences. Washington will also have to register as a predatory offender for the rest of his life.

"This landmark sentence, the longest to date in Minnesota, bolsters Ramsey County's efforts to end the enslavement of young women and girls in the commercial sex trade in our community," Ramsey County Attorney John Choi said in a written statement.

The Washington case is itself a prime example of just how sprawling sex trafficking can be, authorities said. "This is just a microcosm of what we know is going on across the state," St. Paul police Cmdr. John Bandemer said.

The Washingtons were on police radar for years — one was a registered sex offender for five years — but the case against them didn't coalesce until a 15-year-old victim informed her grandmother, who reported it to police in October 2012.

Bandemer said police suspect the brothers are linked to about 50 victims going back about 10 years. The uncles are linked to more victims going back decades.

"We just couldn't prove some of the stuff that happened so long ago," said Bandemer.

The men were convicted of crimes that occurred in the past few years, including posting hundreds of online ads selling sex with several women who were trafficked as far away as Ely, Minn.

"For survivors in Minnesota and throughout the country, this is something that says, 'We take you seriously,' " said Lee Roper-Batker, president and CEO of the Women's Foundation of Minnesota. "This is [perpetrators'] wake-up call."

The group gave $100,000 to St. Paul police and the county attorney's office that was partly used for the case.

Washington's defiance Thursday was not unprecedented. He also refused to cooperate with a presentence investigation, which evaluates a defendant's state of mind and criminal history. "I feel like it's against my will," he said.

Attorney Tyler Bliss served Thursday as standby counsel for Washington, who represented himself at trial and sentencing. Washington had said he did not want to be represented by the public defender's office because he wouldn't be able to choose his attorney, and didn't want a female attorney.

Bliss told the court that Washington refused to meet with him or discuss the presentence investigation.

Nathanson based her sentences on a presentence investigation conducted for Washington in 2002, and what she had from the current case. Court records show that Washington was 10 when he first entered the criminal justice system.

"It makes dramatic to this court that in a lot of ways, we have failed you," she said.

Still she didn't let Washington off the hook. She rebuked him for failing to complete sex offender treatment.

After he was sentenced, Washington was given some legal forms. He dropped them on the floor.

When the judge ordered Washington to pick up the papers, he didn't budge.

Chao Xiong • 612-270-4708

Twitter: @ChaoStrib