Human rights violations in prisons are nothing new. But what happened last year at Nagoya Prison is alarming. Six prison guards, including a deputy warden, stand accused of physical abuses that resulted in the death of an inmate and caused severe injury to another. On the first day of their trial earlier this week, all but one defendant denied the charges, saying that they had not used a restraining device -- a leather belt with manacles -- to punish the prisoners for disobedience and that the "accidents" had occurred in the line of official duty.

The death of one prisoner is attributed to abdominal injuries and blood-flow obstruction because of excessively tight cinching of the leather belt. The other prisoner suffered internal bleeding that is said to have required more than two months of treatment. Prosecutors must find out exactly what happened in the prison.

Investigations have revealed that leather restraints have been used at other prisons as a means of punishment, but these are not the only cases of prison brutality. In an incident that occurred in 2001, also at Nagoya Prison, a guard fatally abused an inmate by shooting water from a high-pressure fire hose into his anus.