Veronica Hilda Theriault has pleaded guilty in the Adelaide District Court to deception and dishonesty charges over offending that took place in 2017.

Theriault, of Claremont in Western Australia, says she was mentally ill at the time of offending and had recently stopped using her prescribed medication.

But prosecutors on Monday said that was a lie, and the author of a medical report might be called to give evidence on her condition.

Theriault wrote a fake resume to secure a role as chief information officer at SA's Department of Premier and Cabinet between May and August, 2017.

She had her brother, Alan Hugh Melville Corkill, write a false reference claiming she was a senior leadership official with 20 years of experience.

Theriault later hired Corkill on contracts that earned him more than $23,000 in three weeks.

Stephen Apps, for Theriault, previously told the court his client was affected by bipolar disorder throughout the hiring process and her employment in the department.

He said the government had failed to screen Theriault's documentation, and "blind Freddy" could have recognised her ploy.

Corkill, who pleaded guilty to similar offences, was handed a suspended sentence in December.

The case will return before Judge Michael Boylan in May.

Australian Associated Press