There has been a lot of discussion in the Australian media recently about the introduction of an Australian Bill of Rights. Such a bill would, presumably, enshrine into the Constitution freedoms such as freedom of speech, freedom of religion, freedom of association, and other freedoms reminiscent of what appears in bills such as the United States' Bill of Rights. While the aforementioned freedoms are certainly essential in a modern democracy, enshrining them into the Constitution brings with it serious problems.
Under Australian law, the High Court is the sole entity with the right to interpret the Constitution. In other words, whatever is the interpretation of the Constitution by the High Court, is the final word. This represents a significant shift in the balance of power. Take for example the freedom of speech. While this is clearly a fundamental right in any credible democracy, it may have limits. For example, should religious extremists be able to use 'freedom of speech' as an excuse for using their influence to incite followers to conduct extremist actions such as hate crimes or terrorist offenses. While it is debatable whether freedom of speech should allow such actions, the point is that it must remain debatable. In other words, the public should be free to debate this issue, form a consensus, and pressure the elected representatives to pass motions based on this consensus. On the other hand, with a constitutionally enshrined freedom of speech, it becomes no longer a debatable issue which can be influenced by elected representatives or the public, but instead becomes an issue which is decided upon by unelected judges, who are accountable to no one, and whose rulings become the uncontested rule of law.
A good example of the pitfalls of constitutional bills of rights is the 2nd amendment in the United States' Bill of Rights - 'The right to keep and bear arms'. 'Arms' is a rather generic term and can be used to refer to anything from pocket knives to fully automatic assault rifles. Gun laws are a very important political and social issue. However, under the US Bill of Rights the interpretation of this amendment is left solely in the hands of the justices. In other words, debate on this issue in the House or Senate is effectively stifled since neither have the right to influence this - only the Supreme Court does. As a result, it is presently acceptable for individuals to posses fully automatic military assault rifles, and neither the House nor the Senate can do anything about it. In a sensible democracy, issues as important as this need to be debated, and ultimately decided by elected representatives, not by unaccountable justices whose views cannot be overruled by the democratic process.
By far the most striking example of the undeserved shift of power away from elected representatives and into the judiciary, is the Roe vs. Wade decision by the US Supreme Court in 1973. In this ruling the Supreme Court ruled that a woman's right to abortion is protected via the right to privacy of the Fourteenth Amendment. This has become one of the most cited and debated rulings in US history. Abortion is an extremely important, contentious and dividing issue in Western societies, and it needs to be debated and acted upon accordingly. However, as was evident in this case, justices sometimes feel the need to take an activist position and interpret the constitution in ways it was never intended to be. Whether you are for or against abortion is not the issue. The point is that abortion is an extremely important topic that needs to be publicly debated and ultimately decided upon by the Parliament, not by the activist judiciary.
To illustrate the fact that a Bill of Rights is not absolute and is open to interpretation by the judiciary, consider a very good example - once again the US Bill of Rights. In the hands of the judiciary the US Bill of Rights did nothing to prevent slavery, nor did it prevent segregation, nor did it prevent the circumvention of habeus corpus during the War on Terror, despite the fact that under a literal interpretation of this Bill such acts would be outlawed.
A final objection to a Bill of Rights, is that it is not flexible - it cannot evolve with evolving social views. What is enshrined in the Constitution is essentially permanent, unless a referendum takes place, which is very rare. In other words, while the views of society may change, the views of the Parliament may change, but what is enshrined in the Constitution does not.
In summary, a constitutional Bill of Rights, by definition, shifts legislative power away from the Parliament and into the hands of the judiciary, which is not elected, not accountable, and whose rulings cannot be overturned. If a politician implements a bad policy, they can be voted out at the next election. When a judge makes a bad ruling, they cannot be. A Bill of Rights is not flexible, and therefore cannot change as social views change. This is a dangerous situation and represents a complete attack on our democratic process and principles. Australia has an impeccable history of allowing freedom of speech, freedom of religion, freedom of association and protecting the rights and views of minority groups - historically, is the US better in these regards? As such there is no convincing reason to shift power away from Parliament and into the hands of the judiciary. Shifting around the power balance, in a system that has worked so well for a hundred years, is a precarious and pointless thing to do.