Census director Graham Jones resigned for "personal reasons" soon after being disciplined and losing pay for handing the contract for preparing the guidelines for letting computer contracts to a firm run by a former colleague, in breach of ONS and Treasury rules.
Cook said Jones only had the power to authorise contracts worth £20,000 but the initial deal with Vogue Consultants was for £26,500. The company went on to acquire work worth £400,000 before internal auditors realised the earlier deal was against the rules.
Vogue was kept on and Jones allowed to stay in his post until it was learned he had also provided information from the 1961 census to the Criminal Cases Review Commission without seeking authorisation. Jones then resigned before being dismissed without any pay off.
Cook also said a payroll contract with ADP Chessington had been "a dogs dinner'' from start to finish. He could not explain why the privatised company had been allowed to slash its initial bid from £1.9m to £1.02m to win the payroll contract.