Manitoba's auditor says adult offenders are being crammed into correctional facilities that defy standards set out by the United Nations and aren't always adequately supervised once they are released.

Carol Bellringer says Manitoba's prisons are more than 125 per cent full. The province has increased capacity by putting bunk beds in rehabilitation spaces and even gyms, but there is no plan to address a shortage that is expected to reach 2,744 beds in five years, she said.

"Their planning was inadequate for the long-term needs," Bellringer said in her annual report released Wednesday.

Overcrowding has led to four offenders being housed in a room slightly larger than eight square metres, Bellringer said. The United Nations calls for single cells and the federal government suggests single cells of just under seven square metres where possible.

Manitoba has no official standards for how big a cell has to be, the temperature, air quality or light, the auditor pointed out.

"Some older cells at the Headingley Correctional Centre were very dim and reached uncomfortably hot temperatures during summer months," she wrote in her report.

Overcrowding also means inmates spend more time in their cells for security reasons, she said. Other consequences include increased tensions, a greater risk of disease and more time spent simply trying to find places for offenders.

Manitoba has the highest adult incarceration rate of all the provinces and the highest rate of adult community supervision, Bellringer said. Of the 10,000 adult offenders in Manitoba, about two-thirds of them are supervised in the community, she said.

She found one-third of risk assessments done for released offenders were late, so some of them were initially treated as lower risk and weren't supervised adequately. In a bid to reduce workload, the province also reduced supervision standards in parts of Manitoba. That resulted in less time spent with an offender to determine risk to the public.

"You put stronger supervision management practices in place, you're going to reduce your risk," Bellringer said. "You do nothing, you're going to increase your risk."

Bellringer recommended the province keep better track of overcrowding, work on long-term planning, set accommodation standards for offenders and improve community supervision.

The government accepted most of Bellringer's recommendations, but also argued it takes a more holistic approach to crime. The NDP wants to shift the focus from incarceration to crime prevention, the Justice Department said in its official response.

"Too often, corrections becomes the last point of intervention for those who have not succeeded in changing behaviours that bring them into conflict with the law," the department wrote.

Finance Minister Jennifer Howard said the government has boosted funding for justice generally and for corrections specifically.

"Now we want to look at how those resources are best being used," she said.