Queensland teachers are being charged for inappropriately accessing Education Department software despite having "absolutely no idea" their actions are illegal, the state's teachers' union says.

One teacher faced criminal charges for allegedly accessing past exam papers stored on the school intranet to help her daughter study, the Queensland Teacher's Union said, in a public submission to the state's corruption watchdog.

The teacher is accused of breaching privacy policies. Credit:Quentin Jones

The woman "had no idea that her actions could constitute a criminal offence", the union said, blaming a lack of clear policy on information access.

The Crime and Corruption Commission is investigating the potential misuse of Queenslanders’ private information within the public sector, in a series of public hearings starting on Monday.