An investigation into 11 suicides at city jails since 2009 reportedly found serious lapses in safeguards meant to protect inmates from hurting themselves.
Documents obtained by the Associated Press show the lapses took place in nine of the cases.
In one instance, an inmate hanged himself from a metal bed that he stood on its end despite a year-old directive to weld all beds to the floor.
A number of reasons are being blamed for the breakdowns including poor communication between mental health staff and guards, sloppy paperwork, and inadequate mental health treatment.
The documents suggest that most of the suicides could have been prevented, and raise new questions about the city's ability to deal with a growing number of mentally ill inmates.
Mayor Bill de Blasio has appointed a task force to come up with better ways of treating the mentally ill both inside and out of jail.