Judges take their lead from Parliament
New law takes the form of a Parliamentary act.
Starting as a bill, the intended legislation must go through several stages in both Houses of Parliament before becoming an act .
The law undergoes constant reform in the courts as established principles are interpreted, clarified or reapplied to meet new circumstances.
Occasionally old laws become outdated, and there is pressure on the government to update them.
The government may also wish to introduce new laws in line with its policies.
During the late 1990s, for example, a series of acts were passed in line with the Labour Government's programme for constitutional reform.
Sometimes new laws are needed to ensure that the UK complies with International or European Law, such as:
The Human Rights Act 1998
The Freedom of Information Act 2000
Before bills are introduced into Parliament there has often been consultation or discussion with interested parties such as professional bodies, voluntary organisations and pressure groups.
Proposals for legislative changes may be contained in government White Papers which may be preceded by consultation papers, sometimes called Green Papers.
These set out government proposals that are still taking shape and seek comments from the public but there is no requirement for there to be a White or Green Paper before a bill is introduced into Parliament.
In 1997 the incoming Labour Government announced its intention to publish more 'draft bills' and encourage pre-legislative scrutiny.
Some bills apply to the whole of the United Kingdom although they may be confined to one or more constituent part of Britain - for example, only to England and Wales.
Following the establishment of a Scottish Parliament and a Welsh Assembly, powers to make legislation in certain areas have been 'devolved'.
However, power in many other areas, such as defence and foreign affairs (known as 'reserved' matters), still resides with the House of Commons.
The Scottish Parliament can pass primary legislation in such areas as agriculture and health.
The Welsh Assembly's powers only allow it to pass secondary legislation in the form of statutory instruments.