Senior NSW Internal Affairs police had found that a detective should be charged with misconduct in relation to his investigation of the Roseanne Catt case, even before her 1991 trial, a Supreme Court inquiry into fresh evidence in her case was told this week.

A 1990 police report recommending that Detective Peter Thomas be charged with threatening and intimidating Family and Community Services officers investigating allegations that Roseanne Catt's ex-husband Barry Catt had abused children was tended in the inquiry before Acting Supreme Court Judge Peter Davidson this week.

Ms Catt was found guilty in 1991 of eight charges including stabbing and attempting to poison her ex-husband and sentenced to 12 years in prison. Barry Catt was acquitted of sexual abuse charges before her trial.

The police department charges did not proceed because Mr Thomas resigned from the police force in January 1991. The matter was referred to the NSW Director of Public Prosecution Prosecutions (DPP) who decided that there was evidence that Mr Thomas had breached Section 117 of the NSW Child Protection Act by wilfully hindering officers in the exercise of their duties, but no charges were laid.

At Ms Catt's 1991 trial, Mr Thomas denied that he had threatened community services officers. Neither the court nor Ms Catt's lawyers were told about the Internal Affairs findings.

On Thursday, Mr Thomas told the inquiry that he had never been told by anyone of the Internal Affairs department's decision to lay charges. He told the court that he had no knowledge until this week of any complaint or misconduct charge being upheld against him before he resigned from the NSW police force.

Evidence was also tended of Mr Thomas's evidence in an arson case against Jake Sourian in 1995, that he had been exonerated of all complaints against him before he left the police force. (Last year, Greens NSW Legislative Councillor Lee Rhiannon told Parliament there should be an inquiry into Jake Sourian's case. Although he was acquitted of arson, Mr Sourian lost all his family's assets as a result of the charges laid against him by Mr Thomas.) Mr Sourian will give evidence in the Roseanne Catt inquiry.

Mr Thomas was also shown a police department letter from May 1989 instructing his superior officer to parade him as a result of a finding that he had wrongfully dealt with exhibits in a case against a friend of Ms Catt, Errol Taylor. Mr Thomas denied he had been paraded or that he was aware of the finding against him.

The decision to parade him arose after a complaint by Mr Taylor, who was arrested by Mr Thomas in 1985 and later acquitted of growing marijuana after his lawyer demonstrated that evidence against him had been planted. Mr Taylor gave evidence in the Roseanne Catt trial about business dealings between Mr Thomas and Mr Catt.

After Mr Taylor gave his evidence, and before the trial was over, Mr Thomas's Brisbane lawyers wrote to Mr Taylor threatening action against him. Mr Thomas this week denied any knowledge of the letter.

Mr Thomas also told the court this week that he was not aware that the Ombudsman had found that he had given false evidence in an inquiry and was "immature" in his approach to the investigation of Ms Catt when he charged her with arson in 1985. The case was discharged.

This week, Mr Thomas told the court he could not recall many aspects of his Roseanne Catt investigation including what evidence he had when he arrested Ms Catt, whether he interviewed some key witnesses and where he conducted interviews.

Mr Thomas was also asked about his evidence in the trial of Peter Bridge, who was acquitted in 1995 on one of the same charges for which Ms Catt was convicted.

When shown a transcript by Ms Catt's barrister, Andrew Martin, of his evidence against Mr Bridge, Mr Thomas said "I was not at Peter Bridge's trial."

Originally published in the Sydney Morning Herald.