Bruce Lehrmann will represent himself in an appeal against the judgment that found he raped Brittany Higgins in Parliament House, as his supporters abandon him and he is left alone to tackle judge Michael Lee’s landmark verdict.

Mr Lehrmann, a law student, lodged the appeal on Friday against findings that Network Ten and presenter Lisa Wilkinson did not defame him when airing an interview with Ms Higgins on The Project in 2021.

The Australian understands Mr Lehrmann will argue Justice Lee denied him procedural fairness, and will claim Ms Higgins’ evidence had serious credibility issues.

He is calling on the Federal Court to set aside the judgment against him, a verdict be made in his favour, and for Ten and Wilkinson to pay his legal bills for the appeal and the defamation proceedings.

The long-awaited judgment of the matter brought by Mr Lehrmann was handed down in April, finding Ten successfully made out its truth defence and proved, on the balance of probabilities, that Mr Lehrmann raped Ms Higgins in the office of Liberal senator Linda Reynolds.

However, Justice Lee found the network failed to make out its qualified privilege defence and acted unreasonably in its treatment of Mr Lehrmann when airing The Project interview.

Mr Lehrmann had until Friday to file the appeal, after Justice Lee extended the usual 28-day window until May 31.

Mr Lehrmann will claim Justice Lee’s ultimate findings were never put to him in cross-examination, and he was therefore ­denied procedural fairness.

He will also argue there were serious credibility issues with Ms Higgins’ evidence, specifically in relation to an image of a bruise she shared with The Project team in the lead up to her interview.

During Mr Lehrmann’s criminal trial, Ms Higgins claimed the bruise was caused during the rape. However, she later admitted the bruise could have occurred earlier in the night when she fell over at a Canberra nightclub.

In delivering judgment, Justice Lee found Mr Lehrmann would have only received $20,000 had he won his defamation fight “because he is only entitled to be compensated for the reputation he deserves”.

But in his appeal, Mr Lehrmann will argue that because Justice Lee agreed Wilkinson’s Logies speech – which delayed Mr Lehrmann’s criminal trial by three months – had impinged in the administration of justice, he is entitled to greater damages.

The Australian understands while Mr Lehrmann had been provided expert advice from top silk Guy Reynolds SC, he ultimately filed the appeal himself and will self-represent in any subsequent hearings.

Mr Lehrmann also sought help from former crown prosecutor Margaret Cunneen SC, who has extensive experience with rape trials. Ms Cunneen, now a criminal barrister, most recently won a sexual assault case for ex-Wallaby Kurtley Beale.

Justice Lee early last month ordered Mr Lehrmann to pay the rumoured $6m legal bills of both Ten and Wilkinson, criticising the former Liberal staffer for bringing the defamation matter based on a “fanciful and knowingly false premise”.

He ruled the broadcaster could recover costs from Mr Lehrmann on an indemnity basis – covering about 90 per cent of its legal bill – in relation to its truth defence, and on an ordinary or party-party basis – about 70 per cent of its legal bill – in ­relation to its qualified privilege defence.

Mr Lehrmann is currently unemployed, and it is unlikely Ten will be able to recover costs.