Canada's outgoing prisoners' ombudsman says "it's time" for the federal government to move on promised reforms he hopes will dampen a rising wave of violence in the nation's penitentiaries.

Howard Sapers, the Correctional Investigator of Canada, said in an interview that when he surveys key indicators after almost 13 years in his office, he sees a harsher prison environment that is harming inmates, staff and public safety.

"It's a hardening of the institutional environment and retreat from some of the fundamental principles of good corrections," said the criminologist, who completes his term on Dec. 31.

"Inmate assaults; increased use of force by staff; increased use of pepper spray ... on most of the measures we've looked at over a decade, they've tended to go up."

Sapers' office has documented a 93 per cent increase in inmate assaults since 2006 in federal jails, and a Canadian Press survey found beatings are also rising sharply in provincial facilities in Ontario, British Columbia, Nova Scotia and Alberta.

On Wednesday, three inmates were seriously injured in assaults by other prisoners during a riot at the Saskatchewan Penitentiary, according to the Correctional Service of Canada. One man serving a sentence for break and enter died in hospital.

Sapers said he sees hope for reforms in the prime minister's mandate letter to Justice Minister Jody Wilson-Raybould, which calls for a review of the criminal justice system and sentencing changes over the last decade to ensure they are "increasing the safety of our communities."

Her mandate letter also calls for more restorative justice and other initiatives to reduce the escalating number of indigenous prisoners.

The letter also mandates the Justice Department to improve "gaps in services" to inmates with mental health issues, while another mandate letter asks Public Safety Minister Ralph Goodale to explore "sentencing alternatives and bail reform."

However, Sapers -- who was the interim leader of the Alberta Liberal Party before his federal appointment -- says he's becoming concerned about the pace of change on these areas.

"It has been a year, and it is time to start seeing the form and substance of that reform through either legislative initiatives, or budgetary initiatives, or policy initiatives, or a combination of the three," he said.

The Office of the Correctional Investigator says that during the decade of the Conservatives' so-called "law-and-order" legislative changes, the net prison population grew by about 10 per cent, or about 1,377 people. The Conservatives' changes included more mandatory minimum sentences and reduced access to parole for some crimes.

According to the Office of the Correctional Investigator, day parole fell by 14 per cent and full parole dropped by 27 per cent over the decade, while there was a slight increase of two per cent in the number of prisoners being forced to serve out their full terms.

The data presented in a recent academic journal article, which uses Correctional Service of Canada figures, also shows that staff use of force climbed from about 1,000 incidents annually in 2006 to about 1,500 last year.

Non-accidental deaths in custody, suicides and attempted suicides all climbed. The use of pepper spray to subdue prisoners more than doubled in the same time period.

Michael Cooper, the deputy justice critic for the Conservatives, said prisoners should feel safe behind bars, but he defended the Harper government's record and argues violence in prisons is a byproduct of more violent gangs and streets being cleaned up.

"As troubling as it is when we see a violence in prisons, part of this is that over the last decade or so, we have seen a lot more violent people put into correctional facilities," he said.

Under the Conservatives, 51 Criminal Code offences were amended to either increase existing mandatory penalties or introduce a new one.

Cooper said rolling back legislative changes because of prison violence is not the answer: "It's important people who are public safety risks need to be held accountable and part of that is ensuring they are kept off the streets."

He does argue for a review of existing policies to see what is working and failing in terms of ensuring staff and inmate safety in the federal prisons.

The Correctional Service of Canada declined to provide an interview on the increased inmate violence.

It says in an email the service has improved intelligence and information systems to guard against violence, and is "implementing population management and mental health strategies," though few specifics were provided.

The email says a new model for maximum-security units has been developed, with "more controlled activities, enhanced security observation and armed intervention capabilities."

The agency says prisoner work locations are being placed in the main circulation area of the prisons to allow "dynamic security" -- a term that means more direct contact between correctional officers and inmates.

The rise of gangs are also cited as playing a key role in the violence by some experts, and the Correctional Service says a response is underway.

It says it "aims to provide" gang members opportunities to drop their affiliation, adding "measures" are being taken to stop gangs from dominating federal prisons.

Goodale declined an interview, saying in an email changes to the criminal justice system and sentencing reforms are still being reviewed.

The NDP public safety critic, Matthew Dube, echoes Sapers' call for a quicker pace of change to reduce prison populations.

"It is public safety issue. When you're not truly dealing with public health issues, that's when you run the risk of recidivism and that's when the public safety can be put at risk," he said.

"They (the Liberals) have talked about it being important. We'll see if anything comes from that as these numbers continue to come in."