Attorney General Cox sparked anger on Monday when he published only a position statement, rather than the "full legal advice" insisted on by the Commons last month.
Britain's ministers have been forced to back down on Tuesday after parliament found the government was contempt over an order to publish full legal advice on prime minister Theresa May's Brexit deal with the EU.
The contempt of parliament motion tabled by Labour and other opposition parties, including PM Theresa May's confidence and supply partners, the DUP, was passed by 311 votes to 293.
At times, the Attorney General Geoffrey Cox looked overwhelmed with emotion as he listened to colleagues giving character references that might spring him from the contempt charge.
Bercow said there was an "arguable case that a contempt has been committed", and set aside time on Tuesday to debate the issue - just as members of parliament were meant to begin a five-day debate on Brexit itself before their historic vote on the divorce agreement on December 11.
The debates and final vote on December 11 will determine how, and possibly even if, Britain leaves the European Union as planned on March 29, in the country's biggest shift in foreign and trade policy in more than 40 years.
"This house has now spoken and it's of huge constitutional and political signficance", said opposition Labour Party member Keir Starmer.
Tory MPs Peter Bone and Philip Hollobone backed the contempt motion, along with nine MPs from the DUP - who are supposed to be Mrs May's parliamentary allies.
The government suffered another blow just one hour later when parliament also voted in favour of an amendment that will give greater decision-making powers to MPs if, as expected, May's deal is voted down next week.More news: UK's Labour will try to topple May if Brexit deal rejected
Britain's Prime Minister Theresa May answers questions about her Brexit agenda at a Parliamentary liaison committee meeting, November 29, 2018 in London.
It also ordered the "immediate publication" of the legal advice.
This is an extraordinary development, but these proceedings will pale into insignificance next week should Mrs May lose the meaningful vote.
Opening five days of debate on the Brexit deal, May told Parliament that the British people had voted in 2016 to leave the European Union, and it was the "duty of this Parliament to deliver on the result" of the referendum.
Another interesting event today is the notion that Parliament can take control of the process.
Such motions could be used to show a clear majority against going ahead with Brexit on March 29, and mandating the Government to bring forward the necessary regulation to defer the date.
Reflecting on her personal journey, May added: "I have spent almost two years negotiating this deal".
In the most extreme no-deal scenario, shopping bills could rise by up to 10% but even in an orderly no-deal withdrawal, with a transition period, grocery prices could rise by 6%, he said.
"The Government must not be allowed to use this chaotic situation to take focus away from the mess they are making of Brexit".