New Zealand sailor Kerry Hamill, tortured and killed in a Cambodian jail, can never be laid to rest but his brother Rob was yesterday able to see the man responsible for his death, and that of thousands of others, jailed.

Kerry Hamill ended up at the S-21 or Tuol Sleng prison when the yacht he and friends were sailing strayed into Cambodian waters on August 13, 1978.

One crewman, Canadian Stuart Glass, was shot dead. Kerry Hamill and Briton John Dewhirst were taken for interrogation and torture for two months before being killed.

Documented figures put Tuol Sleng's toll at 12,380 but other reports put it between 14,000 and 17,000.

More than 30 years later, Kerry's brother Rob was in court to see 67-year-old Kaing Guek Eav, better known as Duch, sentenced to 35 years' jail for his roles in the deaths.

Mr Hamill said the sentence was not as long as he had wanted but "it's the end of a chapter with an exclamation mark.

"This was a big deal, a historic moment for humanity but in terms of internal family grieving processes ... it never ends".

The family struggled with the loss, with one brother committing suicide.

Mr Hamill has asked Duch's lawyer to try to arrange a meeting, which may happen in the next few days.

"I just want to understand him."

He also wants to press for more information about Kerry, whose body was never found.

The joint international-Cambodian tribunal - on which former New Zealand Governor-General Dame Silvia Cartwright sat as one of the judges - handed down a 35-year sentence but given the time Duch already served waiting trial he would get out in about 19 years, aged 86.

Mr Hamill did not think that was right but said the sentence would give some solace.

"To know that this man who met my brother and all those other people in that prison is now sentenced is some sort of justice."