Where do courts get the power to quash secondary legislation?

In the UK, they can quash secondary/delegated legislation, but where does this come from e.g. HRA/ECHR and if possible the section would be really handy!|||The power goes back hundreds of years, when courts were given limited powers of the king. These powers included the ability to circumvent the law in an effort to find a fair verdict. This is still with us in common law, not only in the UK, but in all countries who follow the English common law (former colonies, such as the US included).