Lawyers for Attorney-General Yvette D'Ath have appealed a Supreme Court judge's ruling in August that the serial offender's risk to the community had abated with age.

Fardon, 69, has a history of attacking females dating back to the 1960s.

He has been under a strict Dangerous Prisoner (Sex Offender) Order since his release from prison in 2013, but will be free in the community when that expires on October 3.

Ms D'Ath is appealing a Supreme Court decision to dismiss her request to extend Fardon's supervision order.

Fardon's victims had said the prospect of him being unsupervised was terrifying.

Solicitor-General Peter Dunning QC, acting for Ms D'Ath, said the Brisbane Court of Appeal should consider what had happened to Fardon's victims when determining his risk.

"In terms of ascertaining what is in fact the risk of this individual," he told the court on Wednesday.

Among his reasons for denying the extension in August, Supreme Court Justice David Jackson said the risk of rapists reoffending "becomes very low after the age of 65".

But Mr Dunning argued too much weight had been placed on the belief an offender's risk to the community diminished with age, noting Fardon had transitioned from high risk to low "recently".

He said Fardon had committed his second sexual offence five months after being released from prison for his first.

"Those features of the respondent's personality that are attributable to this conduct are not things he's been cured of," Mr Dunning said.

But he conceded age had "moderated" Fardon's risk.

Fardon's lawyer, Daniel O'Gorman SC, argued multiple psychiatric assessments had found he was a low risk of offending and had no inclination to sexual deviancy.

Fardon had "sworn off" alcohol and drugs, which were key factors in his offending, Mr O'Gorman said.

"In the last five years, he has been subject of close scrutiny and there has never been a wrong foot stepped whatsoever," Mr O'Gorman said.

"Close scrutiny whereupon, for example, to begin with, even to go the letter box he had to have a leave pass."

The Court of Appeal has reserved its decision.

The hearing came after the Queensland government pushed stronger laws through parliament earlier this month to ensure repeat offenders are monitored for life once released from jail.

A child protection advocate says any risk to the community is not worth taking.

"He has committed heinous crimes, he is out of jail, but it makes absolutely every bit of sense to monitor him because of who he is and if he does nothing wrong that shouldn't be a problem for him," Bravehearts founder Hetty Johnston said.

Australian Associated Press