How effective are the Commons’ two committee systems at scrutinising government policy-making?

In addition to their floor debates, a crucial role of legislatures is to scrutinise government law-making and policy implementation. The House of Commons looks at legislation via bill committees, and its select committees cover each of the Whitehall departments to scrutinise implementation. As part of the 2018 Audit of UK Democracy, Patrick Dunleavy and the Democratic Audit team consider how well current processes maintain parliamentary knowledge and scrutiny of the central state in the UK and England.