It was unreasonable for a jury to convict a former police officer of perjury when it was "crystal clear that he's an honest person", his barrister has argued.
NSW Police sacked former Queanbeyan senior constable Scott White after he was found guilty of lying to the ACT Magistrates Court during criminal proceedings involving partner Sarah Jane Parkinson.
Parkinson, who has since married White, was jailed for three years over offences that involved her falsely accusing her former partner of rape.
Her former partner was charged over the claims and spent about four months behind bars on remand before her deceit was discovered.
During Parkinson's case, in July 2015, White told the court he and Parkinson had "never used condoms at all".
This was despite him having previously told a police officer they had.
The issue was important because Parkinson had staged a crime scene that included a discarded condom wrapper, which she falsely claimed her former partner had left behind after raping her.
When White stood trial on perjury charges in the ACT Supreme Court last November, he conceded he had answered questions incorrectly.
However, Justice Michael Elkaim said White had defended his actions "on the basis that he had not been reckless or had been answering the questions while harbouring under a mistake of fact".
The judge said White claimed he had not considered it relevant to include "the historical use of condoms" in his answers, and that he believed he was only being asked about condom use in relation to a certain type of sexual activity.
"The jury obviously, and appropriately, rejected these considerations as affecting the plain falsity of his evidence," Justice Elkaim said in April as he sentenced White to a wholly suspended 18-month jail term.
White's barrister, John Purnell SC, challenged the former police officer's conviction in the ACT Court of Appeal on Wednesday, arguing the guilty verdict was unreasonable and could not be supported by the evidence.
"It's crystal clear that [White]'s an honest person and of good character," Mr Purnell said.
Mr Purnell said White had given evidence during his trial about issues of recklessness and mistake of fact, but had not been cross-examined about these things "in the true sense".
He argued it had been unreasonable for the jury to reject White's evidence and convict him in those circumstances.
Prosecutor Katie McCann disagreed, saying it had been open to the jury to find that White had been reckless about whether or not his answers were incorrect.
She said any complaint that White's evidence had not been sufficiently challenged could not be made out.
White did not attend the brief appeal hearing, which only lasted about 20 minutes.
Chief Justice Lucy McCallum said she, Justice David Mossop and Justice Berna Collier would reserve their decision on the appeal.
