The UK doesn't have a set back-up plan when a prime minister is unwell, but there are clear procedures in place.
The United Kingdom does not have a written constitution or a specific plan for what to do if the prime minister is too ill to perform official duties.
It's either in or out for a minor royal. A mix and match approach raises too many problems.
A large majority gives the prime minister freedom to dramatically alter the machinary of the nation.
Some argue that a written document would settle difficult questions at times of crisis, but recent evidence suggests otherwise.
The UK Supreme Court's decision will have profound implications for how and why a prime minister can suspend parliament.
The Framers of the Constitution knew their history, and sought to learn from it – and only to repeat the parts they liked.
The UK does not have a written constitution so how can we tell if the government is right or wrong on this point?
Proroguing the parliament for five weeks at a crucial time may prove to be a masterstroke in ensuring a no-deal Brexit.
If MPs aren't sitting in parliament to block no-deal Brexit, can it go ahead anyway?
Westminster has consistently disregarded the concerns of the devolved administrations over Brexit.
Ministers were found in contempt of parliament on December 4 for not publishing the full legal advice on the Brexit withdrawal agreement.
If the UK does secure a deal with the EU, it's not clear that parliament would back it. Here are some scenarios for what could happen next.
Scotland's decision to reject the Brexit Bill may herald a national constitutional crisis.
Monarchs and prime ministers have spent centuries working out which decisions need to be made in public.
It's quite possible that neither the US nor the UK will ever return to normal when it comes to political and constitutional balance.
The Lords won't block Brexit, but here's what could happen when they debate the EU Withdrawal Bill.
How the Article 50 judgment kicked a hornets' nest.
How will the Brexit referendum work? And what distinguishes it from referendums that have been held in Australia?
Yes, the way the EU makes its laws is complex, but it is done democratically.