The union representing Canada's prison guards is calling for an independent public inquiry into the suicide of a female inmate, Ashley Smith.

The Union of Canadian Correctional Officers pushed for the inquiry at a media conference in Kitchener, Ont., where it also released its report on circumstances surrounding the 19-year-old's death. Smith had been in federal custody for 12 months when she choked herself to death at Ontario's Grand Valley Institution on Oct. 19, 2007.

An internal government report tabled earlier this year by Canada's prison watchdog Howard Sapers found that Smith was transferred 17 times between institutions, but never got the mental health support she needed.

The union's report -- which was released Thursday -- said Smith had a history of violence, including choking herself with cloth ligatures. It blames the Correctional Service Canada (CSC)for ordering correction officers not to intervene during her violent episodes, unless she stopped breathing.

"Ashley Smith did not have to die," Pierre Mallette, the union's national president, said in a press release Thursday.

"But at every step of the way, correctional officers were prevented from doing their jobs by senior and local managers at Correctional Service Canada (CSC), who were more concerned about public relations than what was happening inside our institutions for women."

Three correctional officers and a supervisor, all facing criminal charges in connection to Smith's death, were fired after Smith's death.

The report questioned the charges, which union officials say were unjust.

"Any correctional officer across Canada could also face life in prison for doing their job the way these officers were trained and ordered to do," union official Jason Godin said in the press release.

"That's why we see demonstrations of solidarity in front of every single federal institution in Canada today: unlike CSC, we will not abandon these fine correctional officers."

Four other employees were also suspended without pay for 60 days.

The union says it has been pushing for the implementation of a "special handling unit" for high-risk female offenders, similar to one that exists for male inmates.

"Only after the death of Ashley Smith did CSC agree to examine this proposal," Godin said.