The authors examined causes of death (violent & natural) among people in custody in Ontario. They also compared the causes of death in 3 custodial systems (federal penitentiaries, provincial prisons, & police cells). Of the 238 deaths involving men, over half resulted from violent causes. Suicide by strangulation accounted for 90 deaths. Compared with the Canadian male population, male inmates were found to have a higher overall rate of death & a much higher rate of death from violent causes. (31 refs)