What the Supreme Court is
The Supreme Court of the United Kingdom is the country's final court of appeal, with twelve justices. It hears civil cases from across the UK and criminal cases from England, Wales and Northern Ireland. Unlike the American court it cannot strike down laws, because parliamentary sovereignty still holds.
Where it came from
It was created by the Constitutional Reform Act 2005 and opened in October 2009. It took over the judicial role of the House of Lords, ending the centuries-old system of the Law Lords, the senior judges who had sat in Parliament. Supporters welcomed a cleaner separation between the judges and the legislature.
Why it is contested
Critics argue that setting up a separate, named Supreme Court, in its own building, encouraged a more assertive judiciary. The Miller cases, on triggering Brexit and on the prorogation of Parliament, are cited on both sides, as either the rule of law working or judges reaching into politics. This is the institutional face of the legal constitution at the centre of the thesis.