Yes, taxpayers do have protection of the Fifth Amendment when filing their tax returns. However, this has never been interpreted to permit a blanket refusal to give any information on the return.

The Fifth Amendment states:

No person ...shall be compelled in any criminal case to be a witness against himself.

The Supreme Court has held that the privilege against self-incrimination, though founded in the Constitution itself, does not free a taxpayer from the obligation to file an income tax return.27 An individual may, however, refuse to provide a specific item of information if that information would tend to incriminate the individual. For instance, while the amount of income a person received in a year would not be protected, the source of the income might be incriminating and therefore the privilege could be invoked.28

The Court has set out the appropriate procedures to be followed by a taxpayer who wishes to assert the privilege against self-incrimination with

respect to an item which should otherwise be reported on an individual's tax return. The taxpayer should assert the privilege on the return, submitting all other information. If the Internal Revenue Service brings criminal charges against the taxpayer for failure to file a complete return, the taxpayer may raise the privilege against self-incrimination in defense. The judge would then determine whether or not the privilege was justified and, if it was justified, the criminal charges would not be permitted to stand. However, the IRS may re-compute the income tax of a taxpayer who refuses to provide requested data. If the IRS determines from its own investigation that a taxpayer owes additional taxes, it may assess a deficiency. In this case, the taxpayer has the burden to establish the correct liability. Absent evidence supplied by the taxpayer, the assessment by the IRS will be presumed accurate.29 In this respect, the taxpayer may assert the privilege against self-incrimination to prevent being compelled to give certain information, but one result may be a liability for additional income taxes.
 

25 Id at 217.

26        See, Untied States v. Stahl, 792 F.2d 1438 (9th Cir.), cert. den., 107 S.Ct. 888 (1986), United States, v. Ferguson, 793 F.2d 828 (7th Cir.), cert. den., 107 S.Ct. 406 (1986), United States v. Foster, 789 F.2d 457 (7th Cir.), cert. den., 107 S.Ct. 273 (1986), Stubbs v. Commr., 797 F.2d 936 (11th Cir.1986), and Sisk v. Commr., 791 F.2d 58 (6th Cir.1986).

27 United States v. Sullivan, 274 U.S. 269 (1926).

28 Garner v. United States, 424 U.S. 628 (1976).

29 Id.