A new directive on inmate accommodation from the Commissioner of the Correctional Service of Canada appears to more readily accept the practice of double bunking.

The document, obtained by CBC News Network's Power & Politics, dated Feb. 5, 2013, no longer includes the principle that existed in a previous directive that stated "single occupancy accommodation is the most desirable and correctionally appropriate method of housing offenders."

The directive now reads "the Institutional Head … may increase double-bunking cell capacity following consultation with the Assistant Deputy Commissioner, Institutional Operations, and authorization by the Regional Deputy Commissioner. Increase will be done when operationally feasible and take into full consideration of the safety of staff and inmates."

In an interview with Power & Politics, Howard Sapers, the correctional investigator for Canada, told host Evan Solomon the new directive means "double-bunking has become the new norm."

The Union of Canadian Correctional Officers (UCCO) has been vocal in its opposition to the practice, saying two inmates sharing a cell designed for one makes the prison environment more dangerous for offenders and guards alike.

"The closing of three institutions has forced the CSC to change its policy on double-bunking," Pierre Mallette, the UCCO's national president wrote to CBC News.

A spokesperson for the minister of public safety said Vic Toews has not been informed of changes to these procedures.

In the past, Toews has said that dual accommodation is a "completely normal practice" used in many Western countries, and that CSC would continue to use it where appropriate.

But dual accommodation in federal penitentiaries has long been a contentious issue.

"Dropping the principle of single-cell occupancy is cause for serious concern," Catherine Latimer, executive director of the John Howard Society of Canada, said in a written statement.

"Crowding in our prisons endangers both staff and inmates. Ultimately it endangers the public because it impedes the delivery of rehabilitation and reintegration support programs," Latimer said.

The new directive makes it clear that double-bunking should remain a temporary measure and should not exceed 20% of the overall prison population without approval from the Commissioner.

Also, when necessary to house two offenders in the same cell, penitentiary staff must complete an assessment that takes into consideration factors such as the inmates' compatibility, behaviour, gang affiliation and health.