Alo-Bridget Namoa, 19, is one of the first people to be charged with failing to answer questions under the extensive powers of the NSW Crime Commission Act 2012.

Namoa has pleaded guilty to 31 counts that occurred when she was called to give evidence at the Commission earlier this year during an investigation into a suspected planned terrorist act by her 19-year-old husband Sameh Bayda.

She is also facing separate charges of possessing an item and documents connected to a terrorist act, while Mr Bayda has been charged with three terrorism offences.

An agreed statement of facts tendered during a sentencing hearing in Central Local Court on Wednesday said police had found a tactical hunting knife in a sheath and a shahada flag in Namoa's handbag which she told them was for "protection".

Police also allegedly found instructions on how to make a detonator for an improvised explosive device and documents promoting Islamic jihad on Namoa's mobile phone.

During the Commission hearing in February, according to the fact sheet, Namoa said she had begun supporting the Islamic State after downloading and watching propaganda videos of beheadings.

The fact sheet said police had found instructions on Mr Bayda's phone about how to carry out a successful knife attack, including diagrams of human bodies with areas circled in red, and references to particular public places such as restaurants and banks.

Text messages exchanged between Namoa and Mr Bayda suggested that she was going to get pregnant and Bayda was going to die, and that she wanted to "do an Islamic Bonnie and Clyde on the kaffir [non believers]", according to the fact sheet.

But Namoa refused to answer the Commission's questions about whether Mr Bayda was planning to commit a terrorist attack or die in the near future, whether she had helped him plan one or whether she was willing to sacrifice her life.

Her defence lawyer Sophie Toomey told the sentencing hearing her client had no sinister motives and was not trying to defy the state.

"This was a young woman who was in her mind protecting the man she was married to and loved," Ms Toomey said. "Her loyalty while it may have been misguided, your honour, her motives were not sinister."

The court heard that only three people had previously been sentenced for failing to answer questions at a Crime Commission hearing, and they were respectively punished with a good behaviour bond, a community services order and a period of nine months imprisonment.

Ms Toomey said that Namoa was "profoundly vulnerable, possibly seriously mentally ill" when she appeared before the Commission and this offence was the first she had ever committed.

Namoa, the court heard, was being held in isolation as a maximum security prisoner and her mental health had deteriorated.

Ms Toomey said Namoa had been prescribed anti-psychotic medications and doctors had recommended that she needed to be transferred to a needed to a psychiatric facility.

Namoa had told a forensic psychologist that she could watch videos of beheadings "all day" and "liked it" but would never want to harm anyone, the court heard.

But prosecutor Matt Karpin said Namoa could have been motivated by "hatred for or prejudice against a group of people" when she refused to answer the questions.

"The Commission had information in its possession that there was a planned terrorist act. That is a planned act of violence against a member of the community motivated by ideological beliefs that was intended to cause grave fear," Mr Karpin said.

Namoa, who appeared on audio visual link and at times laughed during the court hearing, is due to be sentenced next Thursday.