Earlier this month education secretary Estelle Morris was forced to make a u-turn and abandon her hard-line policy on criminal vetting of teachers. Teachers can now work if they have been checked against the List 99 register of suspected or known paedophiles.

Capita is being paid £400m over 10 years to provide the computer systems and infrastructure for the CRB. It failed to complete the 22,000 checks on teachers and other school staff before the school term begun.

The Home Office is sending a team of experts to the stumbling CRB to deal with the fiasco. Home Secretary David Blunkett said: “I am determined that we will overcome these difficulties to ensure that this vital new public service to protect the public operates effectively.”

But Blunkett refused to condemn the agency. “I am interested in finding solutions. Not scapegoats.”

Capita denied that it was making any money from the contract because of extra staff costs. The delay could have cost schools up to £115,000 a day.

In July, Capita denied allegations of “aggressive accounting” for the companies it bought in 2001.