TRENTON -- A growing criminal inquiry into the sexual assault and exploitation of inmates at New Jersey's only women's prison has prompted prosecutors to call on the state's top law enforcement officials to intervene to stop the abuse, NJ Advance Media has learned.

After investigators uncovered case upon case of staff members allegedly abusing prisoners and exchanging contraband for sex at the Edna Mahan Correctional Facility for Women, the Hunterdon County Prosecutor's Office took the unusual step of asking New Jersey's attorney general and corrections commissioner for a meeting to discuss "remedial action."

The move suggests problems at the prison may be far graver than publicly acknowledged by corrections officials, who have described the indictments of six staff members over the last 18 months as isolated incidents that were being addressed through better training.

An NJ Advance Media review of court documents and public records, along with interviews with inmates and law enforcement sources, points to a widening crisis at the Union Township prison.

Corrections officers and staff have been charged with sexually assaulting prisoners. Inmates say other officers and administrators are complicit in covering it up. And they claim the behavior went unchecked for years before anyone in authority took action to stop it.

In an interview last week at his office, Hunterdon County Prosecutor Anthony Kearns, who is leading the inquiry, declined to confirm or deny details of the case, citing the ongoing investigation and upcoming trial of one of the accused officers.

But the prosecutor disclosed he had requested the meeting with state Attorney General Christopher Porrino and Corrections Commissioner Gary Lanigan to lay out evidence and make the case for changes at the prison.

"As the chief law enforcement officer in this county, with the Edna Mahan correctional institution in my jurisdiction, I have concerns about the behaviors that have occurred there," Kearns said in the interview.

Kearns declined to elaborate, however, and records show assistant prosecutors in his office have fought to keep details of their inquiry secret.

This year, the office twice convinced a judge to seal the criminal records of Edna Mahan staffers who admitted sexually abusing inmates. Those two staff members received plea deals reducing their prison sentences and allowing them to avoid registering as sex offenders under Megan's Law, public documents show.

NJ Advance Media's review found Edna Mahan staff members faced a range of accusations, from pursuing romantic relationships with inmates and offering them food or cigarettes for sex to forcing them to perform sexual acts with threats of violence or disciplinary charges.

One officer allegedly sexually assaulted four women in 2016 alone -- and another victim years earlier. Under state law, any sexual contact between inmates and staff is a crime because prisoners cannot legally consent.

Corrections officials maintain the problem is under control and attributed the spike in arrests last year to the department's own vigilance. But records show many of the accusations date back years and were substantiated only recently.

In January, after NJ Advance Media published a special report detailing a 2010 sex abuse scandal at the prison, state lawmakers called on the Attorney General's Office to investigate.

A spokeswoman for Porrino, Sharon Lauchaire, would not say whether the office had acted on that request and declined to comment on whether the attorney general would review evidence from the investigation.

"The attorney general regularly meets with county prosecutors," she said. "The topics that are discussed are not made public."

'AT MERCY OF SYSTEM'

Edna Mahan is a small prison on a rolling swath of land in Hunterdon County, a place with one of the smallest populations and lowest crime rates in New Jersey. The prison's roughly 650 female inmates are serving time for offenses committed across the state, but when a crime happens behind the prison walls, it falls on the Hunterdon County Prosecutor's Office to investigate.

Kearns, the county prosecutor since December 2010, said the sexual abuse of inmates by sworn law enforcement officers is among the worst crimes imaginable.

The Corrections Department is not under the control of the Attorney General's Office, but Kearns said he sought the office's help in part because of its track record over the years combating human trafficking in New Jersey.

The cases of prison abuse -- which include allegations of coercion or the prohibited exchange of goods for sex -- represent a similar, thorny problem, he said.

"We have always considered these cases very important, because the victim is really at the mercy of the system," he said. "So we take a strong advocacy role in terms of protecting the inmates at Edna Mahan."

That system doesn't always work. In 2010, the Department of Corrections fired three officers after its internal investigators substantiated claims that they had engaged in or helped cover up sex abuse, but lacking DNA and video evidence, the prosecutor's office declined to criminally charge them.

The scandal subsided. Then suddenly, last year, inmates told NJ Advance Media they saw officer after officer marched out of Edna Mahan in handcuffs. Authorities won't say what prompted the wave of arrests.

Court records now show investigators substantiated more than a dozen instances of abuse, including six from 2012 to 2015 -- a period in which corrections officials reported to the federal government they had substantiated just two rape claims among a population of nearly 20,000 inmates at 13 institutions.

Lanigan, the corrections commissioner, declined to be interviewed for this report. But a spokesman, Matthew Schuman, said the department "works to maintain an open and transparent culture in which inmates feel comfortable reporting inappropriate activities.

"If vigilance leads to the discovery of a higher number of undue-familiarity cases, so be it," he said, referring to the term state officials use for cases of improper contact between inmates and staff.

"The department will continue to be proactive in rooting out inappropriate and unlawful behavior and will take appropriate corrective action as needed."

Schuman declined to comment on the prosecutor's meeting request, saying in an e-mail, "We do not make Commissioner Lanigan's meeting schedule public."

ABUSERS' PLEA DEALS

NJ Advance Media's review found prosecutors earlier this year moved quickly to seal the case files of two staff members who pleaded guilty to abusing inmates, keeping from public view all but the most basic details of their crimes and the authorities' justification for the plea deals.

Joel Herscap, 56, a vocational instructor in the prison kitchen, was charged last year after internal investigators looking into tobacco smuggling at the facility found two inmates who claimed he had traded cigarettes for sex.

Senior Corrections Officer Thomas Seguine, 35, was accused of abusing his position to enter into a "romantic relationship" with an inmate.

The two were convicted only on official misconduct charges, however, meaning they won't have to register as sex offenders, and prosecutors waived mandatory minimum sentences in both cases, public documents show. Herscap is up for parole next September and Seguine in April 2019, according to prison records. Their attorneys could not be reached for comment.

Kearns declined to discuss the circumstances of their plea agreements, citing the seal order, but defended the sentences.

"As a part of their pleas, they did give a factual basis regarding their sexual assault of the inmates. That is on the record," he said. "I think, in consultation with the victims, we feel that justice was served in those cases."

One officer, Brian Ambroise, is scheduled for trial on Oct. 3 after he was accused of sexual assault and official misconduct for allegedly having sex with an inmate last September. His attorney, James Wronko, said his client had rejected a plea offer from prosecutors. He declined to comment further.

Three other officers -- Ahnwar Dixon, Jason Mays and Joel Mercado -- also face a range of sex assault and misconduct charges for allegedly abusing inmates. Attorneys for Mercado and Mays said their clients maintained their innocence. An attorney for Dixon could not be reached.

More charges may be coming. Current and former inmates who spoke to NJ Advance Media said there were numerous other officers whose sexual abuse of prisoners was an open secret and the recent arrests had made some inmates more comfortable coming forward.

NJ Advance Media is not identifying several of the inmates, either because they were themselves victims of abuse or because they feared reprisal for speaking publicly about prison conditions.

Kearns declined to confirm whether they were pursuing additional suspects, but said the investigation will remain active "until we are sure we have run every lead, every allegation that we believe is credible, and allow it to come to its logical conclusion."

Corrections officials say they take their duty to protect prisoners seriously, and point to annual audits conducted under the federal Prison Rape Elimination Act, known as PREA, which have found Edna Mahan in full compliance with the law.

But Brenda Smith, a law professor at American University in Washington, D.C., and director of the Project on Addressing Prison Rape, said those standards "are the floor. They're the absolute minimum."

"I think audits are only as good as the day they occurred," she said. "They don't really talk about the long-term culture of an agency. People should not be resting on the laurels of their audits."

The most recent audit of Edna Mahan noted the facility had 93 cameras installed on its grounds and no "blind spots" that could allow someone to avoid detection.

Barbara Clark said they should check again.

"Do you know how many blind spots are in that facility?" said Clark, who was held at Edna Mahan until last October. "Any spots that are in the corners, cameras can't see them. They can't see at all."

Supply closets, for one, were widely known as ideal for sexual encounters in the prison, she said.

Clark, who served nearly 18 years for aggravated manslaughter, was one of the inmates named in NJ Advance Media's special report in January as having been allegedly abused by a fired officer. She is now suing the state over her treatment at the prison.

Schuman, the corrections spokesman, said the department has a wide range of policies to prevent and detect abuse, including unscheduled tours by supervisors and internal investigators and a number of confidential reporting systems.

Clark said the prison's processes for reporting bad behavior by staff are prone to leaks, and often written complaints get lost or intercepted on their way up the chain of command. If an inmate's complaints aren't substantiated, she said, they can face punishment and retaliation.

"These women, they ended up in that place just like I did," Clark said. But just because inmates are behind bars for serious offenses, she added, "doesn't mean we're animals and it doesn't mean we need to be disrespected by officers as well."

"How would they feel if it was their mothers or daughters receiving that treatment?" she said of prison officials. "They wouldn't like it at all."

S.P. Sullivan may be reached at ssullivan@njadvancemedia.com. Follow him on Twitter. Find NJ.com on Facebook.

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