These generally have the power to interpret a written constitution and determine federal questions as well as being a final court of appeal in some areas of law, she said. The new UK Supreme Court, due to begin hearing cases on 1 October, will have power to determine devolution questions, and will also have a “responsibility to select those cases that will enable it to set the law in a new direction”.

The House of Lords, like Supreme Courts in other jurisdictions, has taken a lead role in developing freedom of expression laws, she said, for example, in the case of Campbell v MGN [2004], where the rights of supermodel Naomi Campbell were protected above the right of the Mirror newspaper to reveal details of her treatment for drug addiction.