Harper said he would let the arguments between lawyers about the inquest's focus play out without interference.
Smith died five years ago at the Grand Valley Institution for Women in Kitchener, Ont., where she choked herself to death while prison guards — who were told not to intervene — watched from outside her cell.
Interim Liberal Leader Bob Rae asked the prime minister during question period in the House of Commons on Thursday why the government is continuing to try to limit the scope of the inquest.
"The federal government has consistently taken the position that the jurisdiction of the coroner has to be restricted … and I'd like to ask the prime minister why this is happening," Rae said.
Harper responded that the Smith case is "a terrible tragedy" and said information that has come to light shows corrections officials acted in an "unacceptable" way. He said his government will look at whether additional investments need to be made in the "mental-health aspects of our correctional policies."
Corrections Canada fought the release of the videos showing troubling treatment of the teen from Moncton. The videos were made public Wednesday. One shows Smith being duct-taped to her seat on a plane while being transferred from an institution in Saskatchewan to one in Quebec. Another shows her being held down by a guard in full riot gear while she was injected against her will with a tranquillizer.
Corrections officials do not want the jury at the coroner’s inquest — scheduled to begin in front of a jury in January — to see the videos, arguing that the Ontario coroner has no jurisdiction to delve into the federal prison system.
Smith was first incarcerated at the age of 15 after an incident where she threw crab apples at a postal worker. She was convicted of multiple charges of breach of probation, common assault, trespassing and causing a disturbance.
She racked up six years worth of additional time behind bars for infractions while in youth custody — so many that she eventually ended up serving time in the federal adult prison system.
During the year she spent in federal custody, Smith was transferred 17 times between nine institutions in five provinces.
Public Safety Minister Vic Toews said he has asked corrections officials to co-operate with the inquest, even though lawyers for Corrections Canada and three doctors involved in Smith’s treatment in prison will continue to argue that only the time spent at Grand Valley Institution should be considered.
The hearing on those arguments will resume on Nov. 13.
The release of the videos has renewed calls to keep the mentally ill out of prisons.
Kim Pate, head of the Canadian Association of Elizabeth Fry Societies, said the videos show the treatment Smith received behind bars was abominable, and added that so is what Corrections Canada is doing now by trying to prevent the public from knowing about it.
“The fact that they are spending millions and millions of dollars defending their own actions and trying to hide what actually happened, I think is unconscionable,” Pate said.
“The Canadian public should be outraged.”
Toronto psychiatrist Dr. Irvin Wolkoff said the alternatives to prison are limited for the mentally ill. Prisons become a default for the most difficult cases, he said.
“The trouble is, people like that are at some point too bothersome for society at large, and they stop being of clinical interest,” said Wolkoff.
Family releases documents
Also Thursday, Smith's family released documents their lawyer said showed a "shoddy" criminal investigation into how prison authorities in Quebec had treated Smith.
"When Ashley was alive, the system turned a blind eye to her and ultimately, she was abused right into death," lawyer Julian Falconer said.
The probe followed a plea her family made to the RCMP, saying that Smith had been restrained and given anti-psychotic and other drugs against her will without any legal or medical justification.
The RCMP, claiming it had no jurisdiction, passed the complaint to Quebec provincial police, and three incidents that took place in July 2007 at the federally run Joliette prison in Montreal were investigated.
The provincial police report found authorities used force on Smith "when she behaved contrary to regulation."
While there may have been "deviations from internal procedure," they were minor, no excessive force was used, and the actions did not amount to anything criminal, the investigator concluded.
As to whether the use of sedatives was an abuse, a report by a psychiatrist, Dr. Beaudry, prepared for the correctional investigator, concluded there was no imminent risk to Smith's health or the safety of others.
Falconer called the Quebec police probe "embarrassingly shoddy." He noted police did not even look at Smith's medical file.