A paedophile has been released from prison after serving only a third of his sentence as the Parole Board says there are not the resources to treat him behind bars.

Former Salvation Army officer John Francis Gainsford, 73, who repeatedly abused children under his care, was likely to get the counselling he required outside the prison on parole, the board said.

Critics say an "appallingly large" number of prisoners are not getting the treatment they need before release back into the community.

Gainsford was convicted in December 2006 of 26 counts of sexual offences against young children, including rape, attempted rape and indecent assault. The offending occurred between January 1973 and August 1974 when he was manager of a Salvation Army children's home in Temuka, South Canterbury.

He was sentenced to 10 years in prison.

The Parole Board said Gainsford's risk of reoffending was assessed by a psychologist as "medium to low", and he was considered ineligible for treatment in a group child sex offender programme.

The board said it had been recommended that Gainsford see a psychologist for individual counselling in prison to address his risk of reoffending.

"We are advised that there is immense pressure on the specialist resources needed for this counselling [in prison], with waitlists and therefore no prospect of counselling within the reasonably foreseeable future," the board said.

"On the other hand, we anticipate that he will be able to obtain the assistance of equivalent counselling in the community."

The Department of Corrections said it gave priority for individual counselling to offenders with a greater likelihood of reoffending.

"In the case of offenders who are considered to be at a lower risk of reoffending, it may be most appropriate for them to be released on the condition that they attend a programme or other relevant activities in the community," said acting director of psychological services Nikki Reynolds.

"We believe that we currently have an appropriate level of resources for counselling and psychological interventions with offenders."

The Howard League for Penal Reform said it seemed unusual that a prisoner would be released as early in his sentence as Gainsford "but it appears that the Parole Boardfeels treatment on the outside is a better option than continued detention in prison without treatment".

Ken Clearwater, who has met several of Gainsford's victims in his role with the Male Survivors of Sexual Abuse Trust, called the decision to release Gainsford early "pathetic".

"These were kids. But what happens is that when all this goes to court, they are adults. So people see them as adults, and forget about the damage that was done to them as children."

Requirements of Gainsford's parole are that he completes any treatment/counselling as recommended, and does not have contact with any person aged 16 or younger, unless with an approved adult.