TRENTON — Most of the attacks happened inside the supply closet. Away from workers or security cameras. A dark space that Vanessa Falcone tried desperately to avoid.

Ms. Falcone was an inmate at the Albert M. “Bo” Robinson Assessment and Treatment Center, a 900-bed halfway house here that is at the vanguard of a national movement to privatize correctional facilities.

She was assigned to the cleaning crew, under the supervision of a janitor. One night in 2009, he ordered her into the closet.

“He took his pants off and grabbed my hair and pushed me down,” Ms. Falcone, now 32, said in an interview. “That started a few weeks of basically hell.”

Finally, she told a senior guard that she was being sexually assaulted, according to internal reports written by the guard.

She was immediately transferred to another halfway house. The janitor was dismissed. And that is where it ended.

State officials and prosecutors did not conduct an inquiry into the allegations or the halfway house, which is run by Community Education Centers, a company with close ties to New Jersey politicians, including Chris Christie, who became governor in 2010.

“They shipped me off to another place like it never happened,” said Ms. Falcone, who had gone to prison for forging prescriptions.

Located next to a highway in an industrial stretch of Trenton, the Bo Robinson center is supposed to represent the new thinking in corrections. To save money, the state releases inmates early from prisons and turns them over to privately operated halfway houses.

These facilities are not the street-corner halfway houses of the past. They have hundreds of beds and are promoted as therapeutic communities with a focus on preparing inmates for society.

Yet Bo Robinson, behind its walls, often seems to embody the worst in the prisons it was intended to supplant. Imagine a sizable penitentiary, filled with inmates, some with violent records, but lacking the supervision that prevents such places from falling into bedlam.

The New York Times, during a 10-month investigation of New Jersey’s system of state-regulated halfway houses, put together a portrait of life in Bo Robinson from dozens of interviews with inmates and workers and a review of hundreds of pages of internal reports, court filings and state records.

Inmates are housed in barracks-style rooms, not cells. At night, one or two low-wage workers typically oversee each unit of 170 inmates. Outnumbered and fearful, these workers sometimes refuse to patrol the corridors.

Robbery, sexual assault, menacing of the weak — in the darkness, the inmates’ rooms turn into a free-for-all.

Inmates regularly ask to be returned to prison, where they feel safer, workers said.

Government agencies pay millions of dollars annually to Bo Robinson for drug counseling, yet drugs have been so rampant inside that when one group of inmates was tested, 73 percent came up positive, Mercer County records show.

The government requires that Bo Robinson provide therapy, job training and other services, but current and former workers said they had neither the skills nor the time to do so.

They said that as a result, they falsified inmate records. The workers said that when they did deliver these services, they had to do so haphazardly, knowing they were accomplishing little, if anything.

Inmates, who wear street clothes rather than prison uniforms, are herded by the dozens into large rooms. Workers read monotonously from self-help literature.

A churning of staff members deepens the problems. Managers and low-level employees regularly quit or are dismissed, according to interviews with more than 15 current and former employees.

The impact of the disorder is far-reaching. Each year, thousands of inmates from state prisons, and several hundred from county jails, pass through Bo Robinson.

Community Education charges government agencies roughly $70 a day per inmate, about half the cost of a spot in state prison. Over all, New Jersey has made Community Education an integral partner in the corrections system. Roughly 5,200 inmates and 2,500 parolees went through its halfway houses last year, the company said. The state’s prisons now hold 24,000 people.

State officials said halfway houses like Bo Robinson were susceptible to drug use and other misconduct because they had fewer restrictions than prisons and no correction officers. But the officials said the state regulated the facilities effectively.

Community Education said it would not comment on the assertions of former Bo Robinson workers quoted in this article. The company said several of the workers had been “discharged with cause,” though it would not say which ones.

In an interview last week, Robert Mackey, a senior vice president at the company, acknowledged that there had been problems at Bo Robinson. But he said the company had addressed them with new training for workers and enhanced security measures.

“There are things that have gone wrong here; there are events that have occurred,” Dr. Mackey said. “But to focus on a number of events or the report of some employees that are in my opinion not representative of the hundreds of people that are working in this state, I think, is a miscue.”

Asked about staffing at night, he said, “It has not been problematic for us.”

“I’m getting people wanting to come to work and feeling safe in the environment,” he said.

Still, several former correction officers said they were startled by conditions at Bo Robinson, where they took senior jobs. They had retired from the New Jersey prisons and said they were accustomed to orderly correctional facilities. They said they could not understand why the state tolerated Community Education’s management of Bo Robinson.

“It’s not a safe environment — not safe for inmates or for staff,” said Robert Brumbaugh, the former deputy security director at Bo Robinson, who went there after working 25 years for the Corrections Department. “It was horrendous.” Mr. Brumbaugh said he had informed Community Education’s executives about problems at Bo Robinson many times and had also told state regulators.

Such troubles are not limited to Bo Robinson, and have plagued the halfway house system for years, the Times investigation found.

Bronislaw Szulc, a former senior state official in charge of investigating conditions at halfway houses, said he had filed reams of reports to the Corrections Department documenting drug use, violence, lax security and escapes at Bo Robinson and other facilities.

Mr. Szulc, who retired from the department in 2010, said top officials in Trenton had often ignored his reports, rarely held the halfway houses’ operators responsible and demanded that he soften his critical findings. “I was told to stand down and ease up — not to go after things so hard,” he said.

When the State Commission of Investigation examined gangs in New Jersey’s correction system in 2009, it discovered that the facilities most plagued by gang activity were halfway houses, not prisons.

“Beyond outright threats and shakedowns, even time on a facility’s pay phones was found to be controlled and sold by gang members,” Lee C. Seglem, assistant director of the state commission, said in an interview.

Senior officials seem to have done little to address the problems, even when they have reached the upper echelons of state government.

For years, one of Community Education’s supporters in the Corrections Department was the deputy commissioner, Lydell B. Sherrer, who supervised the halfway-house division.

In January, Mr. Sherrer pleaded guilty to federal extortion charges. In exchange for bribes, he had been promising to arrange jobs at Bo Robinson and other halfway houses.

The company said it had never hired anyone he had recommended.

Drugs and More for Sale

In August 2009, officials in Mercer County, which includes Trenton, became concerned about drug use at the Bo Robinson center and decided to conduct a surprise drug test of the inmates that the county had sent it.

Of 75 inmates, 55 tested positive for drugs, or 73 percent, according to county records.

Community Education promotes Bo Robinson as a drug-free institution, saying it seizes contraband and teaches inmates to reject drugs. But heroin, cocaine, marijuana and other drugs often seem to be available more and used more in Bo Robinson than in prisons or jails, according to workers, inmates and state records.

“Bo is like the projects,” said Matthew Leibe, who was an inmate there last year. “I’m walking down the hallway from mess and I’m getting approached by everybody selling everything. ‘I’ve got batteries, T-shirts, weed, heroin, coke.’ ”

Bo Robinson, which was opened in 1997 and was named after a former Trenton city councilman, resembles a conference center more than a jail. Inspirational posters line the corridors. It has a lecture hall, a gymnasium and a recreation area.

Some halfway houses in New Jersey allow inmates to leave on work release, but Bo Robinson is locked down. Escapes do occur, though not as frequently as at halfway houses with fewer restrictions. (There have been at least eight escapes at Bo Robinson since 2009, according to state statistics.)

Drugs slip in, however, through the usual channels — stuffed inside cigarette packs or buried in visitors’ clothing. Inmates have even developed a system that delivers drugs by air.

Bo Robinson abuts U.S. 1, and from a patch of highway shoulder, people throw balls over the fence that have been partly sliced open. Drugs are inside.

Low-level workers, who are known as counselors, are supposed to inspect the yard, and sometimes they find the balls. A senior staff member recalled workers’ seizing one filled with 15 bags of heroin. Often, though, the drugs seem to enter undetected.

So at night, the smell of marijuana smoke drifts down hallways known as Patience Lane and Hope Lane.

The state corrections commissioner, Gary M. Lanigan, who was appointed by Governor Christie, said in an interview that the state and the operators of halfway houses were vigilant about drugs.

“A halfway house, we talked about, is a less secure facility, more access to the general public — more ability to move contraband back and forth,” Mr. Lanigan said. “You’re still an inmate, it’s still treated as contraband, and if you’re caught with any type of contraband, you will be charged.”

After The Times began its investigation of New Jersey’s halfway houses last year, the Christie administration said it would improve monitoring of the system. The Corrections Department said this month that since last July, inspectors had conducted 496 “announced and unannounced site visits” at halfway houses.

Bo Robinson and other Community Education halfway houses hire former convicts as low-level staff members. Some perform admirably, drawing upon their own experiences turning their lives around to inspire inmates.

But Charles Muller, a former chief of the special investigations division of the Corrections Department, said he and his team believed that some workers in halfway houses were dealing drugs and other contraband.

“It’s totally counter to helping these inmates,” Mr. Muller said. “You’re preying on them now, and you’re contributing to the fact that they may be using drugs.”

Asked why the state had not cracked down on drugs at Bo Robinson, Mr. Muller said senior officials had never wanted to devote the resources to do so.

Dana Vetrano, a former counselor at Bo Robinson, said the staff had many former prison inmates. She herself was one, having served time for robbery.

“They were from the streets,” Ms. Vetrano said. “They needed a job, they came in from the street, they were hired — that was it. They had no qualifications. Nothing.

“I used to dread going into that place, and it was because of the staff.”

After the drug tests that Mercer County conducted in August 2009, the state took no action against Bo Robinson. But county officials removed the 55 men who had tested positive from the center and returned them to the county jail.

“We think there were staff that were making drugs available to the population,” said Brian M. Hughes, the county executive. “Until that was resolved, it really was not possible for us to keep them there.”

Community Education soon fired several senior staff members at Bo Robinson, including Mr. Brumbaugh, the deputy security director and former correction officer, who had earned a reputation as a whistle-blower because he had highlighted problems there.

Mercer County later returned dozens of the inmates to Bo Robinson.

In May 2011, Mr. Hughes was invited to the White House for a panel discussion, led by Vice President Joseph R. Biden Jr., on ways to prevent inmates from returning to crime after they are discharged. Mr. Hughes said his county was “on the cutting edge of this issue” and praised Bo Robinson, according to a news release from his office.

A month after the White House visit, Mercer County conducted another drug test at Bo Robinson.

Of 73 inmates, 27 tested positive, or 37 percent, according to county records.

Once again, the state did not penalize Bo Robinson. The county withdrew its inmates, then returned them after new assurances from Community Education.

Mr. Hughes, a Democrat, said the county lacked alternatives because Community Education, with its political connections, had cornered the market.

Mr. Christie, a Republican, has long supported the company. His close friend and political adviser William J. Palatucci is the company’s senior vice president. Community Education also has ties to well-known Democrats.

“I understand that; I’m a big boy,” Mr. Hughes said of the political connections. “I wish that there was a lot of competition to a program like Bo’s, but quite frankly, there isn’t.”

Community Education said the county’s drug tests were being misinterpreted. The company said a vast majority of the inmates who had tested positive had used drugs outside Bo Robinson before being admitted. The tests merely detected lingering amounts, the company said.

“Drug use is not known to be an issue at Bo Robinson or any C.E.C. community facility,” the company said in a statement.

Yet throughout this time, state and local officials ignored a glaring discrepancy.

Community Education says it has a rigorous drug-testing program at Bo Robinson. Even as Mercer County’s tests were pointing to widespread drug use, Community Education’s tests were showing the opposite.

Earlier in 2011, for example, the company reported stellar results to officials: Of 114 county inmates tested at Bo Robinson, the company reported, only one came up positive.

‘A Numbers Game’

Soon after Denette Pasqualini, 40, went to work as a counselor at Bo Robinson in June 2011, she realized that her years as a security supervisor at a Six Flags amusement park had not prepared her for the night shift at a Community Education halfway house.

Her supervisors regularly got drunk on whiskey concealed in soda bottles, she recalled in an interview. Several counselors were having sexual relations with inmates.

Ms. Pasqualini, who said she was paid $10.50 an hour, was the only worker on a unit of more than 100 women when one inmate stabbed another with a pen. When Ms. Pasqualini tried to intervene, other inmates held her back, she said.

“I’m like, ‘How could this be?’ ” she said. “If the Department of Corrections ever came in here and saw this unit, they would close this unit down.”

She offered an explanation for the disparity between Community Education’s drug tests and the county’s: Fraud was pervasive at Bo Robinson.

Ms. Pasqualini said counselors regularly warned inmates of impending drug tests or allowed them to take urine cups into bathrooms without supervision. Most frequently, she said, counselors simply doctored documents to say that inmates had passed drug tests when they had never taken them.

“The staff is from the Trenton area and know the inmates from the streets,” she said. “They say: ‘I’m not going to give her a drug test. I know her. I’ll let it go.’ ”

Ms. Pasqualini resigned after five months because the job was too dangerous.

In interviews, four other former workers at Bo Robinson corroborated her assertions about fraud in its operations.

The workers said Bo Robinson often did not have enough staff. But Community Education required paperwork to prove to state and county officials that Bo Robinson was rehabilitating inmates with drug treatment, therapy and other services.

So the workers cheated, and no one at the company’s management objected when case file after case file had identical entries, the former employees said.

“When we had to give a report for the group session,” Cynthia Taylor, a former counselor, said, “we would look at what was said for the last group and cut and paste.”

Ms. Taylor, 55, previously worked in marketing and had no experience in drug treatment or child development when she was hired to deliver five lectures a week on drug and alcohol abuse and parenting.

Ms. Taylor said she was dismissed in May 2009. She said she was told she had violated rules by sharing a sandwich with an inmate, but she said she believed that she had been punished for complaining about working conditions.

“We all understood that it was a numbers game,” she said. “Community Education made money not on how many people they rehabilitated. ‘How many bodies can we get in here and keep here for a certain amount of time?’ — that’s what they were interested in.”

Asked about the allegations by former workers, the company said: “C.E.C. is unaware of any instance in which any Bo Robinson employee has ever complained to senior management that they were overworked, poorly trained or had forged treatment records.”

The deficiencies in drug enforcement and counseling were especially damaging because Bo Robinson serves as an entryway to New Jersey’s system of halfway houses.

When inmates leave state prison, many of them first spend about two months receiving counseling and being evaluated at Bo Robinson or at a Community Education halfway house in Kearny. Then, based in large part upon inmates’ case files prepared by Community Education, state officials determine whether to place them in a long-term halfway house, and in which one.

But the case files were filled with dubious information about inmates’ time at Bo Robinson, workers said.

Derrick Watkins, a former deputy director of treatment, said he had needed to reprimand workers for falsifying inmates’ records. Mr. Watkins said he had once found the same counseling report copied 30 times, with identical entries but a different inmate’s name written on each page.

Another time, a counselor copied a colleague’s progress reports and submitted them as his own. “When I called him in and asked him, he confessed,” Mr. Watkins said. “He may have done that to hundreds of people who came through.”

Mr. Watkins said he was dismissed in 2009, along with much of the senior staff, after Mercer County found that 73 percent of its inmates had tested positive for drugs. He said that of his staff of roughly 15 counselors, perhaps 3 had received training in drug and alcohol treatment.

“If you don’t have the skills to talk about drug treatment, you’re just, for lack of a better word, baby-sitting,” he said.

Using counselors with no more than high school diplomas, as Community Education did, “is not clinically sound,” Mr. Watkins said.

He said Narcotics Anonymous sessions and other counseling sessions sometimes included over 100 inmates and often turned raucous, with inmates shouting, arguing and throwing things, or else sleeping.

At one point, Mr. Watkins said, he discovered that many of the younger inmates who usually scorned these meetings were eagerly attending. When he learned what was happening, he said, he was stunned.

“An older resident comes in my office; he wants to see me,” Mr. Watkins recalled. “He sits down and he says, ‘Mr. Watkins, I’ve got to tell you something, but it’s got to stay between me and you.’ No problem. He said, ‘The Bloods are running the N.A. meetings.’ I said, ‘Excuse me?’ ”

“Instead of drug and alcohol talk, they were talking gang stuff.”

‘A Sexual Predator’

When Vanessa Falcone was growing up in a quiet New Jersey suburb, her world revolved around art classes and violin lessons — Dvorak was her favorite. Her father was a civil engineer. Her future seemed limitless.

But by her 20s, she was a single mother with a young son, working at a Starbucks and feeling overwhelmed. She began abusing pills that she had been prescribed for migraines, and later moved on to heroin. She was arrested on charges of forging prescriptions, and she went to prison.

Eventually, she ended up at the Bo Robinson center.

Assigned to the maintenance crew, she was supervised by a janitor who was notorious for bringing in cigarettes and other contraband for female inmates in exchange for sex, according to inmates, workers and the institution’s records.

The janitor began cornering her in the supply closet and violently forcing her to perform oral sex, she said.

“Once in that closet,” she said, “he would totally have control over me.”

Ms. Falcone said she agreed to be quoted by name because she was angry about conditions in Bo Robinson.

Finally, a security supervisor named Brenda Brown noticed that something was wrong and confronted Ms. Falcone, who told her that she had been assaulted by “a sexual predator,” Ms. Brown wrote in a report.

“He was blocking my exit and holding on to my hair,” Ms. Falcone recounted in a handwritten statement included in the report. “This incident scared me and makes me feel very traumatized and uncomfortable here.”

Within hours, Ms. Falcone was transferred out of Bo Robinson.

Mr. Brumbaugh, the halfway house’s deputy security director at the time, said he had viewed security video that showed Ms. Falcone leaving the closet moments after one of the attacks. She was pale and shaken, he said. He was certain she was telling the truth. “She just looked shocked, like something happened,” he said.

At her new halfway house, a police detective interviewed Ms. Falcone once about the attack but did not follow up.

The Mercer County prosecutor’s office had no record of her or the janitor, who did not respond to several phone messages left by The Times.

Ms. Falcone was released from the correctional system in 2009 and has not been arrested since. She now works as a florist.

Even when prosecutors have brought charges against a worker at Bo Robinson, corrections officials have not scrutinized its management.

Last year, an inmate escaped from Bo Robinson, and when he was captured he told the police that he had fled because a male counselor there had repeatedly raped him.

The counselor, Joseph A. Chase, was later arrested and charged with sexual assault. Prosecutors said the police also discovered drugs in Mr. Chase’s car. The case is pending.

Asked about the two cases, Dr. Mackey, the Community Education executive, said: “They obviously occurred. We responded to them.”

He added, “You are going to find these to be completely uncharacteristic.”

But violence among inmates is also common at Bo Robinson, according to interviews and the halfway house’s records.

Especially at night.

Supervisors regularly reported finding signs of overnight attacks. One memorandum to security guards, referring to a large hole in a wall, said, “It is obvious a body slamming into the wall was the cause.”

Internal reports describe the mayhem in one room in the women’s unit, No. 332, in 2009.

A gang of women was terrorizing other inmates. One gang member was brandishing “a padlock secured in a sock,” a counselor reported.

“Every night I live in fear,” an inmate said in a handwritten complaint.

The other inmates in the room were also frightened. Another inmate wrote, “I have been threatened and sexually assaulted.” A third: “These daily occurrences make my life at Bo Robinson unsafe.”

A senior counselor wrote in a report that a fourth inmate was crying “uncontrollably” because she had been sexually abused by a female inmate known as Gangster.

“I’m afraid to say anything,” the inmate was quoted as saying, “because Gangster is not going to leave me alone.”

Eventually, four women identified as ringleaders were removed from Bo Robinson and returned to prison, but no criminal inquiry was opened, according to prosecutors.

Supervision was so poor that inmates often made a plea to workers.

“They definitely told me, ‘I want to go back to prison,’ ” said Assenka Oksiloff, 50, who worked for most of last year as a G.E.D. teacher at Bo Robinson. “They would tell me that all the time.”

Several former counselors at Bo Robinson said violence was difficult to contain, given staffing levels and a lack of training.

Shannon Donalson, who previously worked as an office temp, said she was hired as a counselor in the women’s section but was frequently asked to work in the men’s.

“I didn’t do it because I didn’t feel safe,” she said. “Why would I want to go and be expected to handle 300 men by myself at night? You want me to go in a corner with all these men where you might not be able to see me? No, that’s crazy.”

Futile Appeals for Change

Robert Brumbaugh thought he had found a way to convince executives of Community Education Centers that the staffing at Bo Robinson was inadequate. He escorted them through the institution, showing the many areas without workers.

They nodded in agreement, he recalled, but nothing was done.

“They don’t want to spend money,” he said.

Community Education has repeatedly said it handles inmates far more ably than state prisons do, at roughly half the cost to the government. Former correction officers like Mr. Brumbaugh can offer their own comparisons.

At 6 feet 1 inch and 235 pounds, Mr. Brumbaugh is an imposing figure. After three years as a Navy aircraft electrician, he joined the New Jersey Corrections Department in 1982, inspired in part by an uncle who was a police officer.

Mr. Brumbaugh retired as a corrections chief in 2007, then became deputy security director at Bo Robinson. He spent two years there and now provides security for a precious-metals refinery in Pennsylvania.

During his first week at Bo Robinson, he was patrolling the yard with one or two other workers and more than 400 inmates — a ratio far higher than what a prison would allow.

“It was a rude awakening,” Mr. Brumbaugh said. “How can you see if they’re moving contraband or recovering contraband tossed over the fence?”

As Bo Robinson expanded, to 900 beds in 2008 from an original 320 beds in 1997, it was accepting more inmates with histories of violence, Mr. Brumbaugh said.

“The standards got very loose,” he said. “Are there inmates who shouldn’t be there? Absolutely.”

Mr. Brumbaugh said he regularly received calls at home late at night about disturbances, something that rarely happened in the prison system.

He said counselors at Bo Robinson were given about eight days of training, with little time dedicated to security. New Jersey correction officers receive about 15 weeks of training. Of the counselors, he said, “at least half of them were scared to death.”

He so distrusted his own staff, Mr. Brumbaugh said, that he relied upon inmates to inform on workers who were dealing drugs or engaging in other misconduct.

Executives of Community Education knew about many of these problems, he said, but when they gave tours of Bo Robinson to officials or potential investors, everything was staged.

Hallways were scrubbed and painted. Visitors were kept far from the men’s units, the rowdiest areas.

“You couldn’t possibly get a good picture of what’s going on unless you went in there on a normal day,” Mr. Brumbaugh said.

One of his top aides was Ms. Brown, a retired corrections captain.

Ms. Brown has a military bearing after a career spent in uniform. She keeps her hair short and her Nissan as clean as it was when she drove it off the lot. In an interview, she said she took the job as a security supervisor at Bo Robinson because she believed that inmates deserved the second chance Community Education promised.

When counselors first told her that they were afraid to walk Bo Robinson’s hallways at night, she scoffed. But she said that she, too, soon felt that fear.

“Once you got caught, there was really nowhere to go,” she said. “There was no real security.”

Ms. Brown said she had to accept that she could do little to prevent inmates from selling drugs, skipping treatment lectures and having sex in the showers. (Whether the sexual activity was consensual or not, she said, she rarely knew.)

One weekend night in November 2009, Ms. Brown recalled, she was again scrambling to do the work of three people when she received a report that a visitor had smuggled in a roll of $20 bills in her shoe.

While investigating, Ms. Brown said, she heard that several inmates were injecting heroin in the bathroom.

She found one of them.

“I could tell that he was so high that I went to the nurse’s door and I started banging,” she said. “He needed medical attention.”

She could not bear it any longer.

“It felt out of control,” she said. “I didn’t want someone dying on my watch.”

She resigned and never went back.