Sinn Fein MP John Finucane is suing a DUP councillor over unfounded Twitter allegations of supporting and promoting the IRA.
Defamation proceedings against Marc Collins relate to postings made during the 2019 Westminster election campaign.
Senior judges today allowed Mr Finucane’s appeal against a previous preliminary decision on the meaning pleaded in defence of his action.
Proceedings relate to a tweet published in November 2019 amid media coverage of banners which attacked and made allegations about the Sinn Fein representative and members of his family.
At the time Mr Finucane was standing as the party’s candidate in the General Election for North Belfast - a seat he went on to win.
The Court of Appeal heard that a posting on Mr Collins’ Twitter account claimed: “He supports and promotes the IRA, he isn’t innocent by any means.”
In June last year the DUP politician was suspended from Mid and East Antrim Borough Council for eight months after a watchdog standards investigation found he had breached the code of conduct.
He now faces a High Court lawsuit seeking damages over the contents of the tweet.
A statement of claim by Mr Finucane’s lawyers contended it had a defamatory meaning that he not only supports and promotes the IRA, but also condoned acts of terrorism perpetrated by the organisation.
Defences of justification and honest comment have been raised, along with a dispute about the connotation to the words.
At a previous hearing a judge allowed an added meaning which introduced Mr Finucane’s membership of Sinn Fein as part of an amended defence to the action.
Counsel for the MP challenged that development, contending it was impermissible and equated to an “absurd” assertion that every representative or supporter of the party also promotes the IRA.
Ruling on the preliminary appeal, Lady Chief Justice Dame Siobhan Keegan confirmed Mr Finucane’s membership of Sinn Fein can be raised as part of any defence of justification or honest comment.
But she held that the defendant was wrongly permitted to specifically refer to the party as a pleaded meaning of the tweet.
Setting aside the earlier judicial order, Dame Siobhan stated: “The political identity of the appellant is relevant to the defences of justification and honest comment but should not have been included as a meaning.
“Having established the proper meaning, we remit the remaining legal issues for determination to a different judge who can manage the case to trial. “
The Chief Justice added: “We express no view on the overall merits of this case.”
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