Court of Appeal judges have refused permission to appeal in the latest court hearing of a high-profile defamation action brought by a Conservative Party donor against a former Tory MP.

Today’s hour-long hearing centered on an appeal application against a judgment and order earlier this year in which businessman Mohamed Amersi sought to amend his particulars of claim.

Amersi, who has donated more than £500,000 to the Conservative Party, brought a defamation claim against former MP Charlotte Leslie saying documents that contained defamatory allegations against him were shared with and forwarded to influential individuals.

The case was brought after Amersi dropped a claim against Leslie that the memos breached data protection law. After dropping that case, he told the Financial Times he would ‘seek vindication’ through libel proceedings.

In a judgment in June, Mr Justice Nicklin said that, in conducting proceedings in the way he had, Amersi had ‘exhausted’ any claim he might have, adding ‘this claim is at an end’. 

Hugh Tomlinson KC, for Amersi, told the court today that the judge had conducted a ‘serious harm trial without oral evidence’.

He said: ‘First instance judges are required to engage in active case judgment. The judge went too far in [the] case management he engaged in this case. The claimant was, in substance, cut off from pursuing his vindication and he is entitled to it of course.’

David Price KC, a solicitor advocate acting for Leslie, told the court the hearing ‘did not have the benefit of the judge’s response to the grounds of appeal’.

He said: ‘My overriding submission is that on all grounds as a matter of law it is not going to get the claimant anywhere on the facts of this case. It is very unfair on my claimant who has had this litigation hanging over her and her company for years.’

He told the court: ‘There are from time to time, [problems] in defamation claims, and we do need robust case management. It is quite clear what the judge is saying and he has a right to make [those points].’

Lord Justice Underhill and Lord Justice Warby refused permission to appeal. Reasons would be circulated 'shortly'.

Following the judgment, Leslie described the outcome as a vindication for free speech. 'I’m delighted the Court of Appeal have decided that Mr Justin Nicklin was entitled to dismiss the claim, having found no serious harm to Mohamed Amersi’s reputation from any of the publications, and that "the claimant adopted an exorbitant approach to the litigation." And for me, a three-year nightmare is over.'