Ireland and Ulster rugby player Paddy Jackson looks on as his solicitor Joe McVeigh speaks to the media on Wednesday

Lawyers for Ulster and Ireland rugby star Paddy Jackson have warned of further libel actions over the avalanche of social media commentary on his rape acquittal.

The threat came after Mr Jackson instructed his legal team to start proceedings against a high-profile politician.

Irish senator Aodhan O'Riordain faces High Court defamation proceedings over a tweet sent in the wake of Wednesday's verdicts, which saw Mr Jackson and teammate Stuart Olding cleared of raping a woman after a night out in Belfast.

As the fallout from the dramatic nine-week trial continued:

Mr Jackson's lawyers said they were "monitoring everything", including social media commentary, WhatsApp, Google searches and the protests that have taken place in Belfast, Londonderry and across Ireland;

People using the "IBelieveHer" hashtag were warned it was defamatory, meaning every one of the thousands who have shared it on Twitter is at risk of being sued;

Belfast solicitor Kevin Winters said they were "setting down a marker" and would not hesitate to issue proceedings;

Sources close to the legal teams said they were monitoring online content at all times;

It emerged a juror had posted an online comment on the verdict, and could face arrest and contempt of court proceedings.

Mr Jackson (26) was cleared of rape and sexual assault on Wednesday after a trial spanning 42 days. It followed allegations made by a then 19-year-old woman following a party at Mr Jackson's house after a night out in Belfast in June 2016.

Mr Olding (25) was cleared of forcing the woman to perform oral sex.

Blane McIlr oy (26) was found not guilty of exposure and Rory Harrison (25) was acquitted of perverting the course of justice and withholding information.

It took a jury less than four hours to clear all four men of all charges.

However, social media commentary - described by Mr Olding's lawyers as "unprecedented" - has continued.

Yesterday, Mr Jackson's legal team, KRW Law, confirmed it had launched a defamation action against Mr O'Riordain.

The action relates to a tweet Mr O'Riordain posted about the trial shortly after Wednesday's verdict. The tweet was subsequently deleted.

Mr O'Riordain declined to comment yesterday.

KRW Law said: "On Wednesday, March 28 our client Patrick Jackson was unanimously acquitted by a jury at Belfast Crown Court on unsubstantiated charges.

"During the course of the trial our client and his co-accused regularly sought the protection of the court against the prejudicial excesses of social media.

"Despite Wednesday's resounding declaration, Patrick now finds himself resorting to the Civil Courts in order to seek protective action.

"Regrettably, KRW Law has had no option but to issue Notice of Intention to sue Senator Aodhan O'Riordain for defamatory comments made by him in the immediate aftermath of the jury's verdict."

Marie Hans, senior associate at KRW Law, said: "I can confirm we have issued pre-action libel correspondence against a named Senator in the Republic of Ireland. The legal action relates to a tweet sent to a number of other persons before it was eventually taken down."

Ms Hans added that they are monitoring comments that appear on social media about the high-profile rape case.

She added: "We will not hesitate to repeat similar legal action against anyone, who deliberately or otherwise, sees fit to attack our client. We are examining carefully every item of social media commentary which seeks to challenge the integrity of the jury's full endorsement of our client's innocence.

"High court proceedings will be issued shortly in both Belfast and Dublin."

The news came as solicitors for Mr Jackson slammed the "IBelieveHer" hashtag on social media as defamatory.

Around 1,000 people gathered in Belfast yesterday to protest the outcome of the trial and the handling of the rape case with many taking to social media using the defamatory hashtag. Other protests took place across Londonderry, Dublin, Galway and Cork.

The Belfast rally was organised by Reclaim the Night, a group which campaigns against harassment and gender-based violence. Many held placards showing support for the complainant at the centre of the case.

Ms Hans stated that some of the comments "seek to undermine" the jury's finding.

She told the Belfast Telegraph: "Patrick Jackson was acquitted unanimously by a jury of his peers, who heard all of the evidence throughout a nine-week trial.

"To the extent that the 'I believe her' comments seek to undermine the finding of the jury and imply that Mr Jackson is guilty of the crime of which he has been acquitted, they are defamatory.

"We make no comment on the wider conversation about the manner in which such trials are generally held, but our concern is to ensure that the facts about Mr Jackson are accurately reported and shared.

"The truth is that he was acquitted, and enjoys the same presumption of innocence as any other individual. This is not up for debate or interpretation. It is unquestionably a matter of fact."

Kevin Winters from KRW law said: "We are setting down a marker. We won't hesitate to issue proceedings. Already we see material that is highly defamatory of Mr Jackson and we are examining it now over the next few days." Solicitor Joe McVeigh, who acted for Mr Jackson, said that while people have a right to protest, it is "not for them to tell the jury they are wrong".

"It's not for people on social media to tell the 11 members of the jury that they came to the wrong decision," he said. "In this jurisdiction there have been other rape cases and other sexual assault cases where there have been acquittals this week.

"No one sat at the door in support of those complainants or disagreed with the decision.

"No one included in those cases are famous or have any degree of a public profile. No one felt particularly involved in the outcome of these trials.

"What is it about this trial that is having them react in such an emotional way on social media?" The solicitor urged the public to take a "broader view" on flaws in how the judicial system handles rape and sexual assault cases.

Mr Olding's solicitor Paul Dougan said: "The comments, the posting by people who knew nothing about the case other than what they read in snippets and social media - I have never seen anything quite like it."

Belfast Telegraph