Other arguments against I-File: States that have used free filing systems have had a relatively low usage rate--a federally run program could make auditing easier (and more likely) and it wouldn't necessarily encourage taxpayers to take all deductions possible.

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The program also bars the IRS from auditing the taxpayer for payroll tax issues for those prior years.

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The Office of the Inspector General uses a program called RAT-STATS (like the name) for their auditing.

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