This issue could (ironically) go all the way to the European Court of Justice...
A landmark case in the UK High Court has ruled that UK Prime Minister Theresa May cannot trigger Brexit without putting it to a vote in the House of Commons.
The lawsuit brought by a group Bloomberg describes as "a hairdresser, a finance entrepreneur and others unwilling to be publicly identified" is turning into a controversial case which could test the limitations of the power of the office of Prime Minister in the UK.
What happens now?
The British Government instantly announced it would appeal the decision and the two sides will now prepare for another showdown at the Supreme Court in early December.
"The country voted to leave the European Union in a referendum approved by Act of Parliament. And the government is determined to respect the result of the referendum. We will appeal this judgment," a government spokesperson said after the ruling.
It is unclear if the UK would have grounds to go to the European Court of Justice if its legal appeal is unsuccessful.
If the ruling is upheld it will create a legal mechanism for the House of Commons to overrule the result of the referendum.
While the majority of PMs privately support the UK remaining in the EU - they are likely to face a severe backlash if they defy the democratic wishes of the public.
We could face an interesting situation where Remain politicians representing Leave regions have to decide which way to vote.
This graph from Morgan Stanley reflects the Brexit divide between MPs and suggests that a vote on the article could have enough support to overrule the referendum result if they are prepared to defy the public's wishes.
Should the vote happen - and the public's desires are overruled the 'Leave' campaign could take an unlikely case to the European Court of Justice - asking it to uphold the Leave vote.
The main headline is that today's ruling further muddies the water as the UK prepares its Brexit plans.
While it is unlikely that the vote will be overruled - there is a real possibility that it will be significantly delayed as a series of new legal hurdles arise.
Article 50 says that a state's process of leaving must be done "in accordance with its own constitutional requirements" - but in this case no such requirements exist...