Sir Roger, who was knighted in the new year’s honours list, has first-hand experience of weaknesses in the criminal record checking system.

He had to demand an investigation after the Criminal Records Bureau cleared two potential Barnardo’s employees who he knew had previous convictions.

The offences, including possessing cannabis and threatening behaviour, failed to show up on CRB checks. Sir Roger said afterwards that his confidence in the agency had been dented.

He is now heading the panel of police, child protection and medical experts who will advise the Education Secretary which borderline cases should be banned from working with children through List 99 until a permanent overhaul of the system is in place.

Independent experts will also decide who will be barred from schools under the permanent vetting system to be considered by Parliament next month.

Sheffield-born Sir Roger, 64, began his career in 1965 as a teacher at Aycliffe approved school, County Durham, where he went on to become deputy head. He was assistant head of Durham county council’s social services department from 1971 to 1974 when he moved to Barnardo’s as its deputy director in 1974.