Half of prison inmates experience mental problems

Via Rep Peña, the Justice Department yesterday published a new study finding that a majority of inmates in US prisons and jails have mental health problem (see the DoJ press release), "including 56 percent of state prisoners, 45 percent of federal prisoners and 64 percent of local jail inmates." Reported DoJ:

• 54 percent of local jail inmates had symptoms of mania, 30 percent major depression and 24 percent psychotic disorder, such as delusions or hallucinations.
  
• 43 percent of state prisoners had symptoms of mania, 23 percent major depression and 15 percent psychotic disorder.
• 35 percent of federal prisoners had symptoms of mania, 16 percent major depression and 10 percent psychotic disorder.

It's interesting to me that local jails have the highest percentage of people with mental health problems. I'm not sure I understand why. Any reader thoughts on the subject would be welcome.

UPDATE: A commenter from Sentencing Law and Policy blog rightly points out: "Look closley at the methodology of this study -- it's poor. This is similiar to other studies by DOJ on this topic. For instance, there is no diagnosis in the DSM for "mania" -- mania is a symptom of bi-polar disorder, but not a diagnosis itself. Plus, any DSM diagnosis was allowed (but not via a SCID interview, but through self-report). I could go on and on..."

He's right, IMO. That number sounded high when I reported it. In Texas, to my knowledge, we don't have great statistics on this subject, but estimates I've heard range from 16-22% of inmates having "serious mental illness" of the type that can be diagnosed by a mental health professional - self-reported symptoms of "mania," as in the DoJ study, capture a much broader but less well defined pool of folks.

RELATED: For a grim read, see this report from 2002 (pdf) on how Texas uses administrative segregation - i.e., ad-seg, or 23-hour per day solitary confinement - for some mentally ill inmates literally for years. It was compiled by an expert hired as part of the denouement of the Ruiz litigation.