"We have done a lot of work around controls and improving the proof of identification framework and a huge amount of work around the tax file number database to make sure our information is as accurate as possible, such as if someone leaves the country without deactivating a tax file number. We also flag tax file numbers if we suspect they might be stolen or compromised because it is important to close the creation of identifications as a vehicle to commit fraud."

Education of call center agents in social engineering tricks is also paying dividends.

Monaghan cited a recent example of a call center operative who fielded a call from someone attempting to change an address and bank account details. The worker also heard voices in the background asking the same questions on other calls. A subsequent investigation found an operation "preparing fraud for the tax season."