Although Roseanne Catt was in jail, police began to doubt her guilt. Her case could finally be determined this week, reports Wendy Bacon.

Just before the end of her 12-year jail sentence, senior police reviewing Roseanne Catt's case suddenly became worried. Had Catt - the woman accused of trying to poison, stab and order a hit on her husband - been framed?

NSW police documents obtained by the Herald show the friendship between her husband, Taree car mechanic Barry Catt, and the officer who ran the case, then detective Peter Thomas, figured among these concerns.

The alarm was raised in 2000. By then Catt was the longest-serving woman prisoner in NSW.

Despite these concerns being raised with senior police, Catt stayed in jail 10 more months, until August 2001. Then the Attorney-General asked the NSW Court of Criminal Appeal to reopen her case after a witness - located independently by Roseanne Catt's lawyers - came forward with fresh evidence.

This week the appeal court will receive the findings of Judge Tom Davidson after his 18-month inquiry into the Catt case. The court will then decide whether or not she was guilty.

During the inquiry, NSW police provided support to Crown lawyers who continued to vigorously prosecute the case against Catt.

In 2000 NSW police and department lawyers conducted an internal review of the case after receiving a Freedom of Information request from ABC's Four Corners.

The police documents the Herald has seen show that while reviewing documents as part of the request, Helen Ainsworth - an adviser to senior police - became concerned about the conviction on several grounds.

These included the "closeness of the friendship" between detective sergeant Thomas and Barry Catt, the wrongful disposal of exhibits seized on the day of Catt's arrest and the finding of a pistol in Roseanne Catt's house.

After the Four Corners' broadcast and a Herald article raised questions about the conviction, the then manager of the Legal Compliance Unit, Rob Koopman, reported 12 grounds for concern on October 24, 2000.

Mr Koopman concluded that Internal Affairs police had genuinely tried to investigate complaints by members of the Department of Community Services about Mr Thomas's behaviour after Catt's arrest in 1989.

They had issued instructions that Mr Thomas be charged with a disciplinary offence but he resigned in January 1991 before this occurred.

The Internal Affairs' 1990 report on his activities was not available to Catt's lawyers at the time of her trial in 1991.

Mr Koopman suggested a further review of the case because "it may be possible that a number of police involved are still members of the service".

Mr Moroney, then the deputy commissioner for specialist operations, was given the October 2000 report. He requested an Internal Affairs assessment.

In December 2000 Internal Affairs sent a confidential report to Mr Moroney and other senior police that agreed with the previous reports and noted another "disturbing aspect to this case is the fact that Mr Thomas conducted the investigation at all, considering his personal involvement with the parties involved".

"It appears that he had a close friendship with Barry Catt," it said. "More worryingly, he had already been involved in an internal investigation following his charging the then Roseanne Annetts with arson following a fire in 1983.

"These charges were dropped due to lack of evidence and there was apparently criticism of Detective Sergeant Thomas's behaviour in the Ombudsman's subsequent report."

In 1985 the NSW Ombudsman found that Mr Thomas had lied when giving evidence in a hearing of a complaint by Catt.

A senior Internal Affairs officer reported that media attention had prompted "an upsurge in public concern over the continued imprisonment of Roseanne Catt".

Originally published in the Sydney Morning Herald.