It's not too difficult to imagine what might catch the ATO's eye, said Thomson Reuters' Terry Hayes.
"Outstanding tax return and activity statement lodgements would be high on the list."
But the ATO said the focus would be moving towards private wealth and trust arrangements.
"For the first time, we are applying our risk differentiation framework to small-to-medium enterprises and highly wealthy individuals to more accurately target individuals who demonstrate risky behaviour," the ATO said in a statement.
The ATO said it would collect account details of bank customers to identify Australian resident taxpayers with offshore bank accounts which may expose undeclared income and/or gains in the 2008-09 to 2010-11 financial years.
The ATO will request the account details from a wide range of banks such as: ANZ, Commonwealth Bank, Westpac, Bank of Qld, Macquarie Bank, Bank of China (Australia) Limited, Citigroup, HSBC, Investec Bank, Rabobank Australia Limited, Citibank and Union Bank of Switzerland.
Approximately 50,000 offshore account records will be matched. A report by the Tax Justice Network claims there could be up to $21 trillion stored away in offshore accounts worldwide.
The data-matching is intended to help the ATO identify any non-compliance with lodgement and payment obligations under the tax laws.
Offshore bank accounts may have been established for legitimate business or other reasons, but the ATO's data-matching may result in a query that taxpayers will have to answer, said Hayes.
"Capital gains tax issues also spring to mind, as does return of rental income, correctly claiming property deductions, ownership of property issues, and more."
Approximately 10.4 million individuals will be matched with the data-matching scheme. In 2011 the ATO prosecuted about 1200 people with tax and superannuation offences.
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