NEW YORK (CBSNewYork/AP) — Sobbing as she read a heart-wrenching hand-written letter about her son, the mother of a mentally ill and diabetic inmate who died after spending seven days locked inside a Rikers Island jail cell announced Wednesday that she had filed a wrongful death lawsuit against the city and its private jail health services contractor.

In the civil rights lawsuit, Beverly Ann Griffin said her 39-year-old son, Bradley Ballard, was denied medication, ignored and neglected by jail guards and medical staff.

At a news conference at her lawyer’s office, Griffin read from the letter, at times wailing, telling those who ignored Ballard they have to “live with what you did.”

“When you took my son away from me, part of me died too,” said Griffin, 61. “I will never be the same again.”

The Associated Press reported Ballard was locked in his cell alone for seven increasingly agitated days in which he was denied some of his medication, clogged his toilet so that it overflowed, stripped off his clothes and tied a rubber band tightly around his genitals – leaving them swollen and severely infected.

Though guards peered in Ballard’s cell dozens of times during his extended lockup, they didn’t venture inside until it was too late, according to investigative documents. They found him unresponsive, naked, and covered in feces with the rubber band on his genitals.

He was taken to a hospital, where he later died.

The lawsuit, which seeks unspecified damages, argues that Ballard’s death was not an isolated incident and that city jails have been unfit to handle mentally ill inmates for decades.

“The level of abuse, indifference and misconduct at the heart of this case is stunning and unconscionable,” wrote her lawyers, Jonathan Abady and Jonathan Chasan. “Over a seven-day period, Bradley Ballard was subjected to mistreatment so extreme that it was the functional equivalent of torture.”

The city’s Law Department said it would review the suit. Brentwood, Tennessee-based Corizon Health Inc., the contracted health care provider, didn’t immediately respond to a request for comment.

The gruesome September 2013 death came six months before another seriously mentally ill inmate died in a 101-degree cell in a similar mental observation unit at Rikers.

In February, former Marine Jerome Murdough, 56, was found dead in a 100-degree jail cell that overheated due to an equipment malfunction. He had been in the psychiatric section of Rikers and was supposed to be checked on every 15 minutes, but sources told CBS 2 he wasn’t checked for four hours.

The details of both deaths were first reported by The Associated Press. The AP stories prompted lawmakers to call oversight hearings and elicited promises for reform by Mayor Bill de Blasio, who appointed a task-force designed to overhaul the corrections system for the mentally ill.

About 40 percent of the roughly 11,500 daily New York City inmates have a mental health diagnosis, officials say. About a third of them suffer from serious mental illnesses such as bipolar disorder and schizophrenia.

Ballard, who family members say suffered from schizophrenia, had been confined to his cell for seven days for making a lewd gesture at a female guard, according to interviews and documents obtained by the AP. For most of that time, the documents showed, he was not given his medication. He was being held in a parole violation for not notifying officials of a changed address.

Jail officials knew of his mental health problems and need for medication to control his diabetes, the lawsuits alleges.

A medical examiner found the main cause of death was diabetic ketoacidosis, which occurs when people don’t have enough insulin and the liver breaks down fat instead. His death was ruled a homicide and prosecutors are investigating.

Mental health staffers visited Ballard’s cell only once before he was discovered to be in distress, the documents showed. None of the 53 officers who worked in the unit in the days leading up to his death had received a required annual refresher course on mental health, the documents showed.

Advocates were planning a vigil on the one-year anniversary of Ballard’s death Thursday.

“You took away a good caring son, an only brother, a concerned uncle, a nephew, a cousin and a friend,” a weeping Griffin said. “Never again I can see his smiling face; tell him, `I love you son.”’

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