They accuse the government of hiding thousands of pages of documentary evidence — much of it from a criminal investigation of St. Anne's in northern Ontario — that might support their claims.
"The federal government is turning its head and doing everything it can to keep the abuse from being uncovered," said Fay Brunning, an Ottawa-based lawyer who acts for some of the claimants.
"(One client) said it feels the same as the past, when the Catholic church was pretending there was no abuse."
Even within a system that has proven a dark stain on Canadian history, St. Anne's residential school in Fort Albany was particularly ugly.
From 1904 to 1976, hundreds of aboriginal children from remote James Bay communities were sent to St. Anne's, one of 140 church-run residential schools in Canada set up to "civilize" First Nations.
Ontario Provincial Police Det. Const. Greg Delguidice led a five-year investigation in the 1990s of abuse at the school.
According to a statement Delguidice gave this year as part of ongoing civil proceedings, students complained they had been whipped, kicked and beaten.
Boys and girls said they were raped or otherwise sexually abused. Children said they were made to eat their own vomit.
The investigation resulted in criminal charges against seven men and women. Five were convicted for offences such as assault causing bodily harm, indecent assault and administering a noxious substance.
His investigation also turned up evidence of an electric chair made by a supervisor, he said.
Victims said they were made to sit on the metal-framed chair with its plywood seat and wires leading to a black box. A supervisor would crank a handle, jolting the bodies.
"The small boys used to have their legs flying in front of them," said Edmund Metatawabin, 65, who said he was twice put in the chair as a seven-year-old in the mid-1950s.
"The sight of a child being electrocuted and their legs waving in front of them was a funny sight for the missionaries and they'd all be laughing."
The girls would be strapped to the chair and jolted for punishment, Metatawabin said in an interview Thursday from Timmins, Ont.
"The cranking of the machine would be longer and harder," he said. "Now, you're being inflicted with real pain. Some of them passed out."
Metatawabin denounced the federal government for withholding evidence the victims themselves presented.
In 2007, to settle a class-action suit, the government set up the "independent assessment process" to adjudicate individual claims and compensate victims of
Canada's residential school system.
To date, about $2 billion has been paid to more than 21,300 victims across Canada, with more than 16,400 claims still in process.
The lawyer for residents of St. Anne's accused the government of wilfully depriving about 100 students of evidence that would corroborate their claims.
"There are no recorded cases granting compensation to anyone for having been electrocuted in this chair at St. Anne's," said Brunning, adding electro shocks amount to torture.
New Democrat MP Charlie Angus, who has written Aboriginal Affairs Minister Bernard Valcourt to complain, said government lawyers seem to be opposing any compensation for those who say they were subjected to electric shock.
Janet Brooks, the head of the government's legal team, did not respond to a request for information.
However, the government, which has not acknowledged an electric chair was used, maintains it cannot release the documentation related to the criminal investigation for privacy reasons.
Andrea Richer, a spokeswoman for Valcourt, said the government takes Angus's complaints seriously.
"Addressing abuse such as this is one of the reasons that the (assessment) process was set up," Richer said. "We will continue to ensure that the department is fulfilling its obligations."
Brunning called Ottawa's position "perverse."
"The federal government clearly knows physical and sexual abuse was proven in courts of law but is refusing to obtain the evidence and/or reveal it," she said.