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produce relevant documentary evidence within her control supports an inference that such testimony and documentation would not support her position. Wichita Terminal Elevator Co. v. Commissioner, 6 T.C. 1158, 1165 (1946), aff’d, 162 F.2d 513 (10th Cir. 1947).
Petitioner’s testimony is neither credible nor sufficient, even if we believed it, to establish that petitioner had reasonable cause for her failure to file timely returns for the years at issue. We sustain respondent’s determination that petitioner is liable for the section 6651(a)(1) additions to tax.
IV. Section 6663(a) Fraud Penalties
If any part of an underpayment on a return is due to fraud, section 6663(a) imposes on the taxpayer filing the return a penalty equal to 75% of the part of the underpayment attributable to fraud. The Commissioner has the burden of proving by clear and convincing evidence that the taxpayer is liable for the fraud penalty. See secs. 6663(a), 7454(a); Rule 142(b); DiLeo v. Commissioner, 96 T.C. at 873. To carry his burden of proof, the Commissioner must prove by clear and convincing evidence that (1) an underpayment of tax exists, and (2) some part of the underpayment is due to fraud. See sec. 6663(b). If the Commissioner proves that any part of an underpayment is attributable to fraud, then the entire
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