Ajitpal Singh, 32, is currently serving the lengthy sentence for his involvement in the sexual assault – an ordeal that terrified his victim.

One of his employees, Randhir Singh, 22, had met the victim on social-networking app Tango and exchanged explicit messages before arranging to meet for sex.

The woman had withdrawn her consent after meeting Randhir Singh at Kippax Fair in September 2013, the Crown said.

Ajitpal Singh had gone with his worker to meet the woman and was waiting in the car. He walked to where the pair were talking in the shopping centre, threatened her child and said he would show her husband the explicit Tango messages.

She went with Randhir Singh to a Belconnen apartment, and was sexually assaulted in the car and then raped in a bedroom.

Once Randhir Singh was finished, his boss went into the room, made more threats and repeatedly raped the woman, confining her in the room for 90 minutes.

Ajitpal Singh was sentenced to a total of 12 years' jail, with a non-parole period of eight years.

His co-offender Randhir Singh was sentenced to eight years and a non-parole period of 5½ years.

Ajitpal Singh has appealed against his sentence, and the hearing took place in the ACT Court of Appeal on Tuesday.

His barrister Ken Archer argued the sentences for each of the individual charges were manifestly excessive.

Mr Archer said the evidence did not support findings by the sentencing judge that the pair had planned the rape, or that his client was the ringleader.

"In my submission, it's guesswork," he said.

He said his client's culpability was the same as his co-offender's, which the Crown had previously argued.

The court heard that his sentences for the three rape charges were the highest on record.

He was sentenced to 10 years for one of the counts, close to the maximum of 12 years, which Mr Archer said was "going too far".

In response, Director of Public Prosecutions Jon White said it was open for the judge to conclude that Ajitpal Singh was the ringleader and planning was involved.

There had been a lot of texting and calling between the co-offenders before they met the woman, including Randhir Singh sending a photo of the victim to his boss, Mr White said.

Ajitpal Singh had organised a second car to take his co-offender and the victim back to the Belconnen apartment, and had threatened her.

One of the appeal judges, Chief Justice Helen Murrell, questioned the finding that Ajitpal Singh was the mastermind.

"It's still unclear to me why he would be characterised as the ringleader," she said.

Mr White replied: "Well, because he was the boss, your honour."

Mr White said Randhir Singh was deferential to Ajitpal Singh, who was his employer at a local trolley-collecting business.

Ajitpal Singh was also older, he said. "He was his boss in every sense."

Chief Justice Murrell, Justice John Burns and Justice Anthony North reserved their decision on Tuesday.

Both co-offenders are expected to be deported on their release.