Norway is set to review a series of controversial child protection decisions involving a prominent expert convicted of downloading hundreds of thousands of images of child sex abuse.

For years the psychiatrist played a key role in recommendations on children being taken into care.

He was given nearly two years in jail by an Oslo court in April.

The decision to review his cases follows a public debate sparked by a BBC investigation.

One family, whose two youngest children were kept in foster care following an intervention by the child psychiatrist, has already been reunited in the past few weeks following a court judgement. The Arnesens’ story featured in the BBC investigation.

Norway’s child protection agency, Barnevernet, has come under attack from some parents and child welfare professionals who say it often takes children into care without adequate justification.

Child protection expert who worked across Norway

The 56-year-old psychiatrist, who is not being named to protect his children, had admitted downloading nearly 200,000 pictures and more than 12,000 videos showing the sexual abuse or sexualisation of children.

The court heard that some images appeared to show infants being raped by adult men.

The psychiatrist, who is appealing against his sentence, said he had been viewing the material for 20 years.

During that time the psychiatrist was appointed to the prestigious 14-member Child Expert Commission, which oversees childcare recommendations throughout Norway. He has also been employed as an expert by various local authorities across the country.

His professional licence to work has been withdrawn but the Board of Health Supervision said after his conviction that they would not be re-examining previous cases he was involved in – despite calls from some parents to do so.

How did Norway respond to scandal?

In June, the children and equality ministry told the BBC it could not comment on the case, and declined a request for an interview.

Now, after considering its “handling of this case during the summer”, it has called on local authorities to look into the psychiatrist’s past cases, and told the health board to work out how that can be done with the involvement of parents. The case raised several issues that had not been previously assessed, it told the BBC.

Borge Tomter, the board’s director of child welfare, said: “I think we are going to assess every case if possible.” But he said he did not yet know how many cases there were.

The psychiatrist himself said 10 years ago that he had been employed as an expert assessor in between 50 and 75 child protection cases.

The Child Expert Commission, in which he was involved more recently, reviews some 750 welfare recommendations every year. The head of the commission, Katrin Koch, told the BBC in July that she had looked into some of his reports and found no cause for concern.

The ministry said no authority had “a complete overview” of the number of cases and “this challenge” was part of the review.

Family’s five-year battle against authority

Inez Arnesen, a mother of eight and local politician from Tonsberg in southern Norway, whose two youngest children were returned to her in August after five years in care, welcomed plans for a review but said: “It has to be done by someone from outside the system who can look at each case with fresh eyes.”

She questioned how parents could take part in the review when most Norwegians did not know the name of the psychiatrist concerned.

Four of her children were put into foster care in 2013 following allegations that she had used physical force on her children, which is outlawed in Norway.

Three years later, a criminal court acquitted her of the charges. Two of her children were then returned – but the youngest two were not. That followed criticism by the now-disgraced psychiatrist of a report recommending that they be allowed to return home.

But last month, the family successfully argued that in light of the psychiatrist’s conviction, that criticism should now be disregarded.

Now her son Christian, 11, and daughter Vendela, aged 12, are gradually readjusting to life with their parents.

“We didn’t cross the finish line when we won,” Inez says. “We still have to get family dynamics back and we have to co-operate with the Child Protection Service. They had my head on the block for five years. I’m willing to cooperate with them, but it’s strange.”

Another mother, Cecilie, whose daughter is in care following a recommendation co-authored by the disgraced psychiatrist, praised the decision to hold a review.

But she said: “I’m not very hopeful. They want people to see that they are doing something, but they are not eager to do it.”

Following the BBC documentary Norway’s Silent Scandal, which examined the implications of the psychiatrist’s conviction, Children’s Minister Linda Hofstad Helleland was criticised by a series of prominent child welfare professionals for failing to defend the system publicly.

In an interview earlier this month she said: “To have the care for a child taken away must be one of the most desperate things a parent can experience.”

But she added: “Where a conflict arises between the interests of the child and the parents, we shall be on the child’s side. On this point I won’t give an inch.”