Uncodified constitution can respond to an ever-changing world and society.
Change can be enacted relatively quickly.
Gradual process of increased prime ministerial power.
Easier post-9/11 to pass anti-terrorism legislation.
Flexible to deal with coalition and minority governments in the event of no majority.
Executive Power (arguments against codification)
Strong government without the constraints of codification can lead the nation in times of crisis.
In the UK; the flexible relationship between Parliament and the Government can change depending on the situation.
Dangers of politicising the judiciary (arguments against codification)
Codification involves the courts, including the Supreme Court in particular.
There would be constant conflicts over the nature of rights and relationships between Parliament, Government, Devolved Nations and others.
Risks politicising judicial nominations.
Argument that unelected judges should not have an extreme level of power over the elected branches.
Human Rights (arguments in favour of codification)
Could provide stronger safeguards for human rights and civil liberties.
Parliament is sovereign and can repeal any human rights legislation, such as the Conservative Government offering a British Bill of Rights.
However; Human Rights Act 1998 proves that this is not the case; Parliament and Judiciary are very much rights-based and would oppose any efforts to attack civil liberties; if citizens approve of Government at an election, then it can be argued that violation of civil liberties is acceptable - such as Terrorism Act 2006.
Executive Power (in favour of codification)
Over-powerful government threatens individual rights, minorities, and the influence of public opinion.
There would be clear 'checks and balances' on the executive.
However; 2010s have seen coalition and minority governments increase the power of Parliament over Government; also argued that if voters give a government a majority, they are representing the will of the people for the executive to have more power.