The wife of a convicted Islamic State recruiter made a gesture appropriated by the terrorist organisation as she left court in Sydney after being found guilty of refusing to stand for a judge.

Moutiaa El-Zahed, 50, was charged with nine counts of engaging in disrespectful behaviour in court, an offence that was introduced in New South Wales in 2016.

After she was found guilty, she sat defiantly with her arms folded as the judge exited.

Then as El-Zahed left Sydney's Downing Centre Court, she raised her right index finger in an Islamic gesture now widely associated with the terrorist organisation.

A Sydney Magistrate said El-Zahed "communicated a lack of respect for the court and the judge" by not rising to her feet when District Court Judge Audrey Balla came in and out of court during a civil hearing in 2016.

"There is no evidence before this court that she genuinely held any religious beliefs [and] there is no evidence that the teachings of Islam compelled this conduct," Magistrate Carolyn Huntsman said.

El-Zahed is the wife of convicted Islamic State recruiter Hamdi Alqudsi, who is serving a six-year jail sentence for helping young Australians travel to Syria to fight.

Moutiaa El-Zahed's husband, Hamdi Alqudsi, is in jail for aiding men to fight with ISIS. ( AAP: Nikki Short )

In 2014, during a counter-terror raid on her home, El-Zahed along with her two sons and her husband alleged they were assaulted by police and falsely imprisoned.

They took the matter to court and the case was dismissed, but during the hearings the court found she knowingly refused to stand when the judge entered the room.

At the time, when the matter was raised, her lawyer advised the court he was "not happy" about his client's decision not to stand.

"My instructions is that she won't stand for anyone but Allah your honour," he said.

Judge Balla warned she could be subject to legal action.

"It may well be that each occasion she does it, may be considered a separate offence," she said.

Dressed in a black niqab, she stood as Magistrate Huntsman entered Sydney's Downing Centre courtroom on Friday.

But upon the magistrate leaving, El-Zahed remained seated and crossed her arms.

Magistrate rejects claim NSW laws were unconstitutional

Magistrate Huntsman determined 2016 legislation making it an offence to be disrespectful in court was constitutionally valid.

In 2016, NSW Parliament passed the Courts Legislation Amendment (Disrespectful Behaviour) Bill which attracts a maximum penalty of 14 days in jail or a $1,100 fine.

The law was the first of its kind in Australia and it applies to all courts in NSW except the Children's Court.

Magistrate Huntsman, in delivering her judgement, rejected defence claims that the legislation introduced under then-NSW attorney-general Gabrielle Upton was unconstitutional

"I reject the defendants contention that section 200(a) is rendered invalid," she said.

The matter will return to court on June 15.