Prof Jones, who specialises in social work, was the leading signatory of a letter sent to the Guardian by the 37 academics, criticising companies that could be expected to bid for child protection contracts.

He told BBC Radio 4's Today programme that potential bidders such as G4S, Serco and Atos had performed poorly on several high-profile contracts, "won't be local [and] won't be focused on this as their core business".