Prisoner suicide

Head against the wall
Hunger strike

“Prisoner suicide is suicide by an inmate in a prison.”

Prisons in the United Kingdom had a sharp rise in suicides between 1972 and 1987, with hanging being the most common suicide method.[1]
A study found that 47% of the deaths in Finnish prisons were suicides.[2]

Large percentages of those who commit suicide in prison do so after having recently received mental health services.[3]
The suicide rate in U.S. federal prisons is lower than the average suicide rate among the general population.[4]

Pretrial detainees tend to have higher rates of suicide than other inmates, and suicides occur most commonly in isolation cells.

The most common time for suicides to occur is in the early morning hours.[5]

Suicidal inmates are sometimes put on suicide watch. In the United States, liability can arise if jail and prison officials demonstrate deliberate indifference toward a prisoner’s suicidal tendencies, as suicidal inmates are regarded as being in need of medical care.[6]

See also
Guantanamo Bay detention camp suicide attempts 
Capital punishment in the United States#Suicide on death row and volunteering for execution
Philip Markoff
Death in custody
List of prison deaths

1. E Dooley (1990), Prison suicide in England and Wales, 1972-87, The British Journal of Psychiatry 
2. M Joukamaa (1997), Prison suicide in Finland, 1969–1992, Forensic science international 
3. BB Way, R Miraglia, DA Sawyer, R Beer, Factors related to suicide in New York state prisons, International Journal 
6. Roberts v. City of Troy, 773 F. 2d 720 (Court of Appeals, 6th Circuit 1985).