Once again we're playing "I've Got A Secret."  How much does he owe -- $500?  $5,000?  $50,000?  Was the conviction related to tax evasion, so once the criminal case ends the IRS is allowed to step in and make assessments?  Is there a restitution order?  How old is he?  Prisoners can't collect Social Security, but once he gets out the IRS can try for a 15% continuing levy.