As Cambodia moves towards opening its first privately run prison, international experts have warned the government may have misunderstood the concept and cautioned that privatisation likely isn’t the best way to tackle chronic overcrowding in prisons.

At a speech last week, Interior Minister Sar Kheng revealed plans for the first privately built and run prison in the Kingdom, which has more than 17,500 inmates in a penal system with the capacity for 8,500.

Kheng, who cited the use of such facilities in Australia, said upscale lodging at the complex could be rented out to wealthy inmates to generate state income.

However, University of Canberra School of Law and Justice associate professor Lorana Bartels yesterday noted a user-pays system was not how private prisons in Australia and other countries worked.

Private prisons in theory are supposed to save taxpayers’ money, as for-profit owners have an incentive to seek efficiencies.

But in Australia, Bartels said opaque contracts between service providers and the government made it difficult to assess whether private prisons were in fact more efficient than their public counterparts.

“We know that money is changing hands, but we don’t know how much… there’s no way of really saying whether they are achieving this goal,” Bartels said.

“It’s problematic to get on board with a policy initiative where the evidence base is shaky to say the least.”

Dating back to the 16th century, according to one study, for-profit, privately run prisons in their modern form began appearing in the US in the 1980s.

Roughly 10 per cent of American inmates now reside inside private prisons.

The UK and Australia keep the highest percentage of their prisoners in privately run facilities – about 19 and 20 per cent respectively – according to an Australian expert and UK government data.

Private or semi-private models are also used in several other countries, including South Africa, Brazil, Japan and Chile.

The Philippines last year invited bids to build its first private prison and Thailand has reportedly conducted feasibility studies into penal privatization.

In a 2005 paper for Duke Law Journal, Sharon Dolovich, faculty director for the University of California Los Angeles’s Prison Law and Police Program, argued the companies’ profit motive could lead to poor services.

“Absent effective checks, efforts on the part of private prison administrators to cut operational costs could thus lead to decisions that deprive inmates of basic human needs, a hallmark of inhumane punishment,” she writes.

A 2015 study by US research Anita Mukherjee, from the University of Wisconsin, found that prisoners in private facilities were detained longer, with operators able to achieve greater profit when holding more prisoners.

Australia National University criminology professor Roderic Broadhurst pointed to moral concerns over whether private companies should control an individual’s punishment, particularly if wealthy prisoners could pay for better treatment.

“What effect might this have on deterrence?” Broadhurst wrote, via email. “The better approach is to… see if you can divert low risk offenders away from costly prisons and try to reduce sentence length via early release schemes such as parole.”

Cambodian prisons offered squalid living conditions to those without the ability to pay for comforts, according to a report by rights group Licadho last year, which noted the “inordinate” use of pre-trial detention.

Human rights lawyer Keo Bunthea said the government should fulfill its own responsibility to prisoners in Cambodia before it thinks of farming out the service.

“They need to provide adequate services for all inmates, not just the wealthy,” Bunthea said.