Tommy Robinson broadcast reports that encouraged “vigilante action” and “unlawful physical” aggression against defendants in a sexual exploitation trial, according to the judges who found him guilty of contempt of court.

The full decision of the high court, released on Tuesday, explains their reasons for ruling against the former leader of the English Defence League (EDL) , whose real name is Stephen Yaxley-Lennon.

Robinson, 36, from Luton, Bedfordshire, had denied breaching a reporting ban by livestreaming footage of defendants arriving at court. He insisted he had only referred to information already in the public domain. He is due to be sentenced later this week.

After sitting at the Old Bailey in London last Friday, Dame Victoria Sharp, president of the Queen’s bench division, and Mr Justice Warby produced a three-page judgment setting out their findings.

“We are entirely satisfied that [Robinson] had actual knowledge that there was an order in force restricting reporting of the trial,” the judges concluded. “He said as much, repeatedly, on the video itself.”

Robinson was found to have committed contempt by breaching a reporting restriction, risked impeding the course of justice and interfered with the administration of justice by “aggressively, and openly filming” the arrival of defendants at court.

Commenting on the impact of Robinson’s actions, the two judges said: “The dangers of using the unmoderated platforms of social media, with the unparalleled speed and reach of such communications, are obvious.

“[Robinson] was engaged in the agitation of members of the public in respect of what he presented as a serious threat to society. His words had a clear tendency to encourage unlawful physical or verbal aggression towards identifiable targets.

“Harassment of the kind he was describing could not be justified … There was plainly a real risk that the defendants awaiting jury verdicts would see themselves as at risk, feel intimidated, and that this would have a significant adverse impact on their ability to participate in the closing stages of the trial.”

In another section, the judges noted that in the video Robinson “approves and encourages vigilante action. We are sure that what [he] said in this passage will have been understood by a substantial number of viewers as an incitement to engage in harassment of the defendants.”

Sharp and Warby added: “If the court were to condone the live broadcast of these defendants being aggressively confronted as they arrive at court, in conjunction with prejudicial commentary and exhortations to engage in harassment, it would pose a risk to the wider interests of the justice system.”

The judges dismissed Robinson’s defence that what he broadcast was legitimate freedom of expression. Fair trial rights were, they said, qualified free speech. “Here, we are concerned with interferences with the administration of justice that fall short of subverting the right to a fair trial. However, we are satisfied that our interpretation and application of the law of contempt is consistent with the [European] convention [on human rights].”

While awaiting sentencing, Robinson has broadcast a desperate plea for the the US president, Donald Trump, to grant him asylum. “I feel I am two days away from being sentenced to death, in the UK, for journalism – today I call on Donald Trump, his administration, and the Republican party to grant me and my family political asylum in the USA.”