Bruce Lehrmann is appealing a court decision that found him guilty of violently raping Brittany Higgins in Parliament House.

Lehrmann argues there were credibility issues with Higgins and procedural fairness concerns during the defamation case against Network Ten and Lisa Wilkinson.

He disputes the judge's findings and questions the authenticity of key pieces of evidence.

Lehrmann believes the damages awarded were insufficient.

Despite his criminal trial being abandoned, Lehrmann continues to deny the rape allegation and plans to challenge the violent nature suggested.

It remains uncertain how Lehrmann, an unemployed law student, will fund the appeal.

Network Ten and Lisa Wilkinson may seek security for costs due to Lehrmann's financial situation.

The appeal may not require witnesses to give evidence again.