How prisons keep their suicidal inmates on watch

( CNN) The suicide of onetime NFL player Aaron Hernandez in his prison cell is one of several recent suicides of parties in detention, inspiring experts is whether or not these deaths were preventable.

Hernandez, who was convicted of murder in 2015, hanged himself Wednesday morning with a bedsheet confined to his space, according to confinement officials. A Washington state inpatient accused of fatally shooting five people last year also hanged himself this week, and a triple-murder suspect recently fell from the fourth flooring of an Ohio courthouse in an seeming suicide, according to police.

Hernandez was apparently placed on suicide watch in 2015 after he was convicted for the assassination of Odin Lloyd, for which he was sufficing a life sentence without the possibility of parole. But there has been no indication he was on suicide watch. An is looking into his death is ongoing.