Parliamentary sovereignty

The highest power in British democracy is that of the electorate — expressed through its representatives in Parliament. This is the supreme (or “sovereign”) power. Legislation can be used to make any imaginable law. In 1917 Lord Justice Scrutton contemplated that a statute could make “two plus two equal to five”. Some economists, though, have been doing that for a while.

The separation of powers

Rooted in ideas of Aristotle, and popularised by the French writer Montesquieu, this precept notes that there are three types of governmental function: legislative, executive and judicial. If more than one of those is given to one person or agency, it is a threat to the freedom of citizens. Not rigidly applicable in the UK as, for example, the law lords are judicial, but they sometimes “legislate” new law in their decisions.

The rule of law

This is a defining characteristic of civilised democracies. Famously articulated by the Victorian jurist A. V. Dicey, the principle means that everyone, however powerful, must obey the democratically passed law, and no one is above the law. The rules are more important than important people. We are ruled by the rules, not by rulers.

Discharging the standard of proof

For criminal and civil court cases to succeed, those bringing them must prove them to a required standard. In criminal cases, for a conviction, the prosecution must prove its case “beyond reasonable doubt”. In civil cases, the party bringing the action must prove its case “on the balance of probabilities”; in other words that it is more likely than not.

Ignorance of the law is no excuse

If you break the law, you can’t escape the consequences by saying you were unaware of it. Mr Justice Talfourd said in 1850: “The rule is not that a man is always presumed to know the law, but that no man shall be excused for an unlawful act from his ignorance of the law.” Chief Justice Abbott, however, cautiously noted: “God forbid it should be imagined that an attorney, or a counsel, or even a judge is bound to know all the law.”

Better that ten guilty men go free than that one innocent person is convicted

Encapsulated by Sir William Blackstone (1769) as: “Better that ten guilty persons escape than that one innocent suffer.” The horror of an innocent person condemned to suffer as guilty is notorious. King Alfred is reported to have hanged a judge who executed a defendant when the jurors were doubtful about their verdict, “for in cases of doubt one should rather save than condemn”.

Proportionality

A key principle of European and human rights jurisprudence demands that a law should be proportionate to what needs to be done by it. So, in 2005, the European Court of Human Rights ruled that legislation that indiscriminately banned every UK prisoner from voting was a disproportionate measure because it brought that extra punishment on all prisoners irrespective of their crime.

Justice must be seen to be done

Nothing to do with people watching cases from the public galleries. It means that if anything even looks as if it might compromise justice it is unacceptable. If a judge had some shares in a company that would be affected by a judgment he gave, his decision would be invalidated because it might look suspicious, even if he had forgotten about his shares.

Independence of the judiciary

Public confidence in the judiciary requires that judges decide cases according to law and not according to bribery, threats or political pressure. Various rules promote free and fearless judging — judicial salaries are not annually approved by Parliament; judges cannot be sued for any judicial utterances or sacked for their judicial rulings.

Law should not be retrospective

It is unfair to make a law today that applies to the past. Statutes are presumed to apply only prospectively. There are exceptions. The War Damage Act 1965 was passed to apply backwards and stop the Government having to pay compensation for damage resulting from military orders in 1942. Chutzpah perhaps but see (above) parliamentary sovereignty.

Professor Slapper is Director of Law at The Open University. His recent book How the Law Works is published by HarperCollins

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