Whitehall's reliance on ‘hired guns' – specialist interims employed to cover a lack of in-house expertise – has fuelled suspicions that departments have been complicit in tax avoidance, an influential panel of MPs has reported.

An investigation by the Public Accounts Committee (PAC) into ‘off-payroll' arrangements across the public sector, reveals a number of failures led to the ‘shocking' revelation that 2,400 central government staff were being paid through personal service companies (PSC).