Child migrants kept being trafficked from the UK to Australia despite officials knowing that some institutions they were sent to harboured paedophile rings, a UK inquiry has been told.
Dr Margaret Humphreys of the Child Migrants Trust told the child sexual abuse inquiry in London that recruiters were sent to the UK to select children for church and charity-run farm schools in Australia.
"I think we would categorise that now as child trafficking," she said on Friday.
The inquiry is examining the sexual, physical and emotional abuse suffered by thousands of children in care who were sent to Australia, New Zealand, Canada and Rhodesia up to the 1970s.
Among the worst offenders were the Catholic order the Christian Brothers, who ran farm schools in Western Australia, and the royals-backed Fairbridge Society which ran farm schools in NSW.
The inquiry has heard from former child migrants that say they were routinely sexually abused and flogged by staff, were poorly fed, clothed and educated and used as virtual slave labour on the farms.
It's also heard that authorities in the UK and Australia knew of sex abuse scandals at the institutions but no proper inspection systems were in place and the offending institutions were allowed to keep operating.
"It's much clearer now that there was knowledge that some of the institutions were quite clearly paedophile rings," Humphreys told the inquiry.
She said the sexual abuse of even one child should have prompted an inquiry but that didn't happen and hundreds of children were abused.
Humphreys, who in 1993 was awarded the Order of Australia for her work with former child migrants, said a regime of bullying and beatings at the institutions meant children were terrified to complain of abuse.
She said children who ran away and complained to police were invariably not believed and would be returned to the institution where they were often beaten in front of the other children as a warning.
They were left "lonely and isolated" to deal with the abuse on their own, she said.
Humphreys slammed the defence that such abuse was in line with the "standards of the day".
"When was it ever the standards of the day to rape children, to abuse children in this way?" she said.
On Thursday former British Prime Minister Gordon Brown told the inquiry the child migration scheme was a "national disgrace" and the UK government must compensate the more than 2000 former child migrants left before they died.
In 2010 Brown apologised to former child migrants on behalf of the British government for the distress caused to them by the scheme.