A codified constitution is a set of rules that seeks to establish duties, powers and functions of various different institutions of government. They're there to regulate the relationship between and among the constitutions, defining the relationship between the state and the individual. A codified constitution is one in which the main principles underpinning the political system are collected in a single authoritative document. One advantage to having a codified constitution is that it establishes and protects our human rights, as the American constitution does with the bill of rights. Codified constitutions are usually sovereign resulting in the rules that establish our rights are unable to be altered. The UK constitution which is uncodified does not protect our human rights because in the UK parliament is sovereign, not the constitution. This caused the UK to adopt the European convention of human rights in 1973 that was then put into UK law in 1998. The human rights act is still relatively weak as it can be overridden by parliament, as it is sovereign. In 2007 David Cameron pledged to abolish the Human Rights Act, this clearly shows without a codified constitution your rights are severely undermined. A codified constitution allows for a liberal democracy by protecting our Human Rights making it more democratic and advantageous over an uncodified constitution. .
Nevertheless there is little evidence to show that parliament will sacrifice the convention of human rights in order to pass a bill. An example of this is the Terrorism Act in 2006. Tony Blair tried to pass this act to try and extend the amount of time a suspected terrorist could be detained to 90 days. This attempted bill failed and proves the point that without a codified constitution, it is still democratic and can protect our human rights. Another advantage for a codified constitution is that it is written in one authoritative document, which makes it clear and simple.