Common Law

‘Common law’ is a largely Anglo-Saxon principle. It refers to the development of laws through historical usage and tradition. Judges, who occasionally must declare and enforce common law, treat it as any rule of conduct that is both well established and generally acknowledged by most people.

The most important application of common law has concerned the protection of basic rights and freedoms from encroachment by government and/or Parliament. The right of people to free movement and to gather for public demonstrations, for example, are ancient freedoms,  guarded by the courts. So, too, was the principle that the Crown could not detain citizens without trial. For the most part, common law principles have been replaced by statutes and by the European Convention on Human Rights, which became UK law in 2000. But from time to time, when there is no relevant statute, the common law is invoked in courts by citizens with a grievance against government.

 The prerogative powers of the prime minister are considered common law powers. They have never been codified or put into formal legislation. These powers are exercised by the prime minister on behalf of the monarch and include commanding the armed forces, negotiating foreign treaties, calling general elections and making appointments to government.

Donoghue v Stevenson- is an example of Common Law

Common law refers to a body of laws that are based on tradition, custom and precedent. Although the ultimate source of common law is custom, long-established practices that have come to acquire legal status, the body of common law has largely been created and refined by the courts on a case- by-case basis. This occurs through the use of precedent, where judgements in earlier similar cases are taken to be binding on later cases.Therefore, while statute law is made by politicians, common law is sometimes seen as ‘judge- made’ law . Constitutional rules that are based on part of common law include: 

• Royal Prerogative. These are the formal powers of the Crown, and they encompass many of the powers of the prime minister and the executive branch of government. 

• Traditional rights and freedoms. Until the passage of the Human Rights Act, the courts recognised what were called ‘residual’ rights, rights that rested on the common law assumption that ‘everything is permitted if it is not prohibited’.


As with interpretations of statute law (made by Parliament), it is not always clear how the existing laws are to be applied in a particular case. For example, there are laws relating to racial prejudice, discrimination against women and against actions that are likely to incite people to commit crime or to indulge in race hatred. This is all very well, but how should the law operate in specific circumstances? It is for judges to decide this. Furthermore, when such a decision is made, it is expected that any similar cases that arise in the future should be dealt with in the same way. Here the concept of judicial precedent also applies. Once the application of law in specific kinds of case is established, the precedents are known as ‘case law’. Case law is thus established by judicial precedent.

Not all law is made by Parliament. Some law is known as ‘common law’ — rules of behaviour that have developed solely by tradition. In other words, they are common ways of dealing with disputes of various kinds. This law typically relates to such matters as inheritance, commercial practices and, very occasionally, the rights of citizens. Much common law is well enough established for judges to be able to apply it relatively easily. However, from time to time there may be problems in settling disputes for which there is no relevant statute law and no clear common law. When this happens a judge must take evidence and decide what the common law is. This is the third example of ‘judge-made law’. Once again the rule of judicial precedent applies. Examples of common law — laws which are enforced because they always have been rather than because Parliament has passed them — include the following:

● Murder

● Manslaughter

● Common assault

● Misconduct in a public ofce

● Many commercial practices and contract issues

● Laws relating to the rights of non-married cohabiting couple