High Court judges are set to reveal the evidence that led them to rule Tommy Robinson in contempt of court by live-streaming himself "aggressively confronting" men accused of sexually exploiting girls.
Two senior judges ruled Robinson's actions breached strict rules around reporting criminal proceedings, designed to ensure fair trials.
Dame Victoria Sharp and Mr Justice Warby will today give details of the legal basis for their verdicts.
Throughout the two-day hearing, Robinson, on trial under his real name of Stephen Yaxley-Lennon, denied any wrongdoing, insisting he did not believe he was breaking reporting restrictions and that he only referred to information already in the public domain.
A crowd of his supporters gathered outside the Old Bailey on Thursday and Friday reacted in anger when the result was announced, chanting in support of the anti-Islam activist and hurling beer cans at journalists from atop a double-decker bus - which received a parking ticket.
The court heard the "reckless" footage, broadcast on May 25, 2018, saw Robinson urge his followers to harass the defendants on trial for grooming children while the jury considered its verdict.
The video lasted an hour and a half and was viewed 250,000 times after being live-streamed on Facebook.
A reporting restriction was in place which postponed the publication of any details of the case until the end of all the trials involving 29 people.
Announcing their decision, Dame Victoria said Robinson committed contempt by breaching the reporting ban, through live-streaming the video from outside the public entrance to the court and "aggressively confronting and filming" some of the defendants.
She said the content of the video "gave rise to a substantial risk that the course of justice in that case would be seriously impeded" and singled out the confrontation of the defendants as an example.
She added: "In our judgment, the respondent's conduct in each of those respects amounted to a serious interference with the administration of justice."
The 36-year-old from Luton, Bedfordshire, was initially jailed for 13 months after being found in contempt of court on the day the footage was broadcast, but was freed after just two months following a successful appeal calling the original hearing "rushed" and "fundamentally flawed."
The far-right activist appeared on the InfoWars conspiracy channel last week to beg US president Donald Trump to grant him asylum because he could face imprisonment.
He said: “I need evacuation from this country because dark forces are at work."
Robinson is expected to be sentenced on Thursday.
Agencies contributed to this report
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies