RICHMOND, Va. -- Benjamin Wash had a long history of drug addiction and had tried to kill himself at least once before he was booked into the Riverside Regional Jail in Virginia on Nov. 28, 2017. But somehow, he was able to hang himself with a bedsheet two days after he was detained.

Wash was one of 51 inmates who killed themselves in Virginia jails over the past five years.

An Associated Press review of jail and medical examiner records shows that nearly half of those took their own lives within the first 10 days of incarceration, a period experts say is critical for intervention because of the despair many inmates experience when they are first locked up.

"When someone is arrested and brought into jail, it's really a sharp break from their life as they knew it," said Michele Deitch, a jail oversight expert and senior lecturer at the School of Law at The University of Texas at Austin. "Particularly for someone who has not been incarcerated before, adjusting to that environment is very difficult."

Suicide has long been the leading cause of death in jails around the country , reaching a high of 50 deaths for every 100,000 inmates in 2014, the latest year for which government data is available.

The deaths have steadily increased since state psychiatric hospitals began closing in the 1970s, converting jails into makeshift mental health facilities. In recent years, lockups have also been inundated by opioid addicts, who research has shown may be more likely to attempt suicide.

In Virginia, the rate was 40 suicide deaths for every 100,000 inmates in 2014. The aggregated five-year rate for 2014 to 2018 in Virginia was 35 deaths for every 100,000 inmates.

Although state regulations require that inmates have medical and mental health screenings upon admission, those assessments vary greatly across Virginia's 58 local and regional jails.

Jail officials say they do their best to evaluate inmates' suicide risk by interviewing them about any history of mental health issues, feelings of depression or suicidal thoughts. They say they also gather mental health records and reports from any previous incarcerations.

Deaths in Virginia jails came under increased state oversight in 2015 after a 25-year-old mentally ill man died of heart failure accompanied by severe weight loss at the Hampton Roads Regional Jail.

In July, Portsmouth City Jail was placed on probation for a year after the state Board of Corrections found that it had violated regulations requiring medical screening and supervision of two inmates, one of whom killed himself and the other who died of a drug overdose. The investigation found that deputies at the jail did not properly check on the inmates and then falsified jail logs. Both employees were fired.

Undersheriff Marvin Waters Jr. said the facility has expanded the initial screening process for inmates since a new sheriff took over in early 2018. The jail now uses a 43-question medical and mental health assessment and a nurse screens inmates, he said. A new digital logging system makes it impossible for anyone to falsify the intervals at which inmates are checked, Waters said.

Riverside Regional Jail, where Wash killed himself, was also placed on probation in July, for three years, because of his suicide and that of another inmate.

Wash's father, Raymond Wash, said he doesn't understand why his son wasn't monitored more diligently. He said his son had been addicted to heroin for years.

"They should have watched him closer. He wasn't in there but two days, and the next thing I know, two police officers and a chaplain are at my door telling me my son had hung himself in his jail cell," Wash said.

Alex Wesley Tripp hanged himself at the same jail Oct. 31, 2017, less than 24 hours after he was booked on minor larceny charges and drug violations. An investigation found that the jail tier where the 32-year-old inmate was housed was not checked for nearly four hours before he was discovered hanging, despite a requirement that checks be done at least twice every hour. A jail officer falsified log entries to make it look as if the required checks were done on time, the investigation found.

Seven inmates at the Southwest Virginia Regional Jail Authority's four jails killed themselves between 2014 and 2018. Four of them did so within seven days of entering jail, after mental health screenings.

"In many of those cases, we had no indication whatsoever of any kind of mental health symptoms or history," said Mandi Smith-Hixenbaugh, regional manager and director of mental health for MEDIKO, a Richmond-based company that provides medical and mental health services to the jail authority.

The nation's jails are filled with people who need mental health treatment, but the facilities aren't equipped to manage them, said Lisa Boesky, a psychologist who conducts suicide vulnerability assessments in correctional facilities.

"Tragically, as quality mental health care in our communities decreases, the numbers of mentally ill and potentially suicidal individuals entering ... jails across the country will continue to increase," Boesky said.