Marcus Stanford, 25, who pawned Ms Scott's engagement and graduation rings, delivered the apology on television shortly after he was released from prison.

"I want to say sorry for what I've done and for the hurt I've caused the family," he told Channel Nine. "For now I hope I don't cause any more trouble." He said he had done "a really stupid thing".

Stanford was sentenced to 15 months' jail last month after pleading guilty to an accessory to murder charge but was released on September 8 because of time already spent in custody.

His brother, Vincent, raped and killed Ms Scott, 26, on Easter Sunday last year. The murder took place on school grounds in the town of Leeton in western NSW.

Ms Scott was declared missing, her body found in a national park days later. Vincent sent Ms Scott's rings and her driver's licence to Marcus, who was living in South Australia.

Marcus pawned the rings for $705 dollars and used some of the money to pay for a flight from Sydney to Adelaide after visiting his brother in jail.

A detailed psychologist report obtained by Fairfax Media last month said Marcus Stanford had attempted suicide in prison.

The report said he had abused alcohol and cannabis before his role in the cover-up, smoking up to eight joints and several cones a day.

Vincent Stanford is due to be sentenced next month.

NSW Premier Mike Baird ordered a review of Marcus's sentence but the Department of Public Prosecutions did