[fifthvirginia]

It is IRC 6103, Confidentiality and disclosure of returns
and return information.

http://www.gpo.gov/fdsys/pkg/USCODE-2011-title26/pdf/USCODE-2011-title26-subtitleF-chap61-subchapB-sec6103.pdf

[Principled]

Thanks - have looked at both and do not find the penalty if guilty....