A former juvenile inmate has filed a lawsuit alleging mistreatment stretching back to the 1990s at the facility today known as Long Creek Juvenile Detention Center in South Portland.

Matthew Keene, 36, of Standish was detained at the facility through the second half of the 1990s, from when he was 13 years old through his 18th birthday when he was transferred to an adult facility, according to the lawsuit filed in October. The South Portland detention facility was called Maine Youth Center at the time.

Keene’s lawsuit alleges that center staff practiced excessive use of restraints and isolation as inmate punishment. Isolation could last for days or weeks on end, he said. The lawsuit alleges that those practices caused severe mental stress that affect Keene’s mental health to this day.

“[The] plaintiff was subjected to excessive use of isolation in a manner which repeatedly violated the statutory standards for its use, was negligent, was imposed for purposes of punishment, was imposed with deliberate indifference to its impact on plaintiff’s health, was employed in a manner which represented a substantial departure from accepted professional judgment, and violated plaintiff’s Constitutional rights,” the suit states.

The suit also claims that the facility didn’t provide inmates with proper access to mental health treatment or educational opportunities.

In addition to the Maine Department of Corrections, the lawsuit names as defendants nearly 30 former corrections officials and Maine Youth Center staff, many of whom are only listed by their last names.

A message sent to DOC Commissioner Joseph Fitzpatrick wasn’t immediately returned Sunday.

[Staff shortages plague ‘dumping ground’ for youth with mental illness]

It’s unclear why Keene waited until 2017 to file the lawsuit, but the facility has come under increased scrutiny during the past year. In November 2016, Charles Maisie Knowles, a 16-year-old transgender detainee, hanged himself at the detention center and died in a hospital several days later.

Earlier this year, three 18-year-old inmates escaped from a Long Creek camping trip and stole an SUV before being arrested, according to police. Long Creek’s superintendent resigned in March citing “personal reasons” shortly after being placed on leave.

Just last week, an independent report called on the state to completely overhaul its youth prison system, citing low staffing and high populations of inmates struggling with mental health issues that have created “ dangerous and harmful conditions.”

[Report urges state to overhaul Maine’s entire juvenile justice system]

Corrections officials have publicly acknowledged that they aren’t equipped to handle the large number of mentally ill teens in the facility.

In 2004, the state reached a $600,000 settlement with another former Maine Youth Center inmate whose charges of excessive restraint and isolation led to a management shake-up in the state’s juvenile corrections system. That inmate, who was only identified as Michael T., also stayed at the facility in the 1990s.

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