Two men who sexually abused young boys placed in their foster care have been sent to prison.
The couple were approved as foster carers in July 2003
Ian Wathey, 41, was jailed for five years and his partner, Craig Faunch, 32, for six years after being found guilty of sex offences last month.
After sentencing the pair, from Pontefract, West Yorkshire, a judge criticised Wakefield social services.
She said it was "quite incredible" police were not involved at an earlier stage and demanded an explanation.
Wathey and Faunch were found guilty following a two-week trial at Leeds Crown Court of abusing four boys aged between eight and 14.
During the trial, the court was told the couple had taken a photo of a boy in their care while he was urinating. It was sent to Wakefield Council's social services department by the youngster's mother.
Social workers decided the men had been "naive and silly" for taking the photo after hearing their explanation that they had used the picture to embarrass the boys into closing the toilet door, which they kept failing to do.
Judge Sally Cahill QC said if the council had involved police at that time it may have prevented further abuse taking place.
She said to Wathey and Faunch: "Once you realised social services would not take any action and believed your ridiculous story about why you had taken it, you went on to abuse others in your care, believing yourself safe from the authorities."
The men were using the boys for sexual gratification within months of being approved as carers in July 2003, the court heard.
The judge said neither of the men had shown any "empathy, remorse or any responsibility for their actions".
Referring to Faunch's abuse of a 14-year-old boy, she said: "You, Craig Faunch, chose to victimise and abuse that boy, showing the very depths in my view of what you are prepared to do.
"You saw him as the ideal victim. You are presented as a couple but this is not about homosexuality, it is about abuse of trust."
Faunch was convicted of two charges of making indecent photos of a child. The court was told that he used a camcorder to film two naked eight-year-old boys in the shower.
He was also found guilty of five counts of sexual activity with a 14-year-old boy.
Wathey was found guilty of four charges of sexual activity with a 14-year-old boy and encouraging a child to watch sexual activity.
He was cleared of two charges of sexual activity with a child.
The court was told neither had been in trouble with the police before and were approved as foster carers after checks and training.
When the pair are released they will be on licence for three years and have to attend a sex offenders' programme. They are also banned for life from working with children.
After the men were convicted three weeks ago, Wakefield Council commissioned a full independent inquiry.
The council's Service Director for Children in Need, Kitty Ferris, said it would respond to the judge's comments once the results of the inquiry were known.
She said the inquiry will look at whether the council correctly followed policies and procedures and whether its level of intervention was appropriate.
Ms Ferris added: "The allegations made against Mr Faunch and Mr Wathey were referred to the police as quickly as possible and were subject to a joint investigation by the police and social services under the safeguarding procedures. This investigation led to the prosecution of the couple.
"The council has offered support, where appropriate, to children who have been affected by this case."