Some youths held in Northern Territory detention centre cells that lacked toilets have resorted to trying to urinate out the windows, a royal commission has heard.
One detainee defecated in his pillow slip after an Alice Springs Youth Detention Centre officer refused to take him to the toilet, lawyer Corrie Goodhand said.
Former Queensland Corrective Services director-general Keith Hamburger, who led a scathing review into the NT corrections system, said it was a horrible situation.
"I think it's an intolerable situation where a person in captivity, I guess, hasn't got control over the capacity to go to the toilet," Mr Hamburger told the NT child detention royal commission.
"We were told that some detainees actually urinated or tried to urinate out of the window of the cells because they either didn't want to ask or they could have been denied, I don't know whether that is the case.
"It's just unconscionable that we would put children in that position."
Mr Hamburger's review found the Alice Springs centre's accommodation was unsuitable for young people in detention, party because there were no toilets in the cells.
The review team was told toilets were being constructed in cells, he said on Tuesday.
Ms Goodhand said there was no access to water in some cells at the Alice Springs facility and the Don Dale Youth Detention Centre in Darwin, forcing detainees to ask officers for drinking water.
Mr Hamburger said the situation was terrible and wrong.
Footage of six young offenders being tear gassed and spit hooded at Don Dale sparked the royal commission.
One, an Aboriginal boy then aged 14, was held for 17 days in Don Dale's behaviour management unit in August 2014, the inquiry heard.
He was kept in the small concrete cell for 23 hours each day, with no air conditioning or fan, his barrister John Lawrence SC said.
Mr Hamburger said that treatment was terribly wrong.
"It couldn't be defended in my view."
Some of the youths in the Don Dale footage are expected to give evidence to the commission's public hearing in Darwin over the next week.
Dylan Voller is threatening to go on a hunger strike because he fears repercussions from prison guards at the Darwin Correctional Centre if he testifies, his mother Joanne says.
Ms Voller says some guards at the adult jail who used to work at Don Dale have been threatening her son and have made him terrified about appearing before the commission.
"I have never seen my son so scared in all of his life," she said in a statement on Tuesday after visiting her son.
Senior counsel assisting the commission Tony McAvoy SC has said special arrangements are in place to protect vulnerable witnesses, including allowing them to keep their identities secret and give evidence during closed sessions.
Commissioners Margaret White and Mick Gooda will visit the former and current Don Dale facilities and Darwin watch house on Wednesday.
