Taxpayers who are required to pay a penalty but fail to do so will receive a notice from Internal Revenue Service (IRS) that they owe the penalty. If they still do not pay the penalty, the IRS can attempt to collect the funds by reducing the amount of their tax refund in the future. However, individuals who fail to pay the penalty will not be subject to any criminal prosecution or penalty for such failure. The Secretary can not file notice of lien or levy on any property for a taxpayer who does not pay the penalty. http://www.bingaman.senate.gov/policy/crs_privhins.pdf So, if I owe the government as per usual it would seem they have little recourse if I refuse to pay their fine.