Although the UK Parliament is sovereign and its executive is powerful this does not mean that either institution has unfettered power. The British constitution contains a number of checks and balances to ensure that power is neither exceeded nor abused. In particular, central government is accountable in political and legal terms.
Political accountability
Parliament’s powerhouse, the House of Commons, is accountable to its electors. At a general election constituents decide which political representatives they want as their MPs and legislators.
The government is drawn from this parliament and it is a constitutional convention that the government is accountable to Parliament for its actions. If the House of Commons were to pass a vote of ‘no confidence’ in the government a general election would be called and a new parliament and government would result.
Ministerial responsibility extends beyond decisions that a minister actually takes, or even knows about. Under the Carltona principle central government officials may act in their ministers’ names without any formal delegation of authority, but when an official so acts it is the minister who must take responsibility both to Parliament and to the courts.[1]
Legal accountability
Ministers are accountable to Parliament for what they do in terms of efficiency and policy, but they are responsible to a court for the lawfulness of what they do.[2] For this purpose the courts developed a system of administrative law, which is exercised by way of judicial review. On a judicial review the court will ask itself whether the impugned decision was lawful or unlawful, namely was the decision within the limits of the powers granted. Judicial review is thus a fundamental mechanism for keeping ministers (and other public officials and bodies) within due bounds. The process and powers of judicial review are explained elsewhere.
[1] Carltona Ltd v Commissioners of Works [1943] 2 All ER 560, CA.
[2] R v Inland Revenue Commissioners ex p National Federation of Self-Employed and Small Businesses Ltd [1982] AC 617, HL, Lord Diplock.