I would probably not go back and recalculate my taxes for previous years just to have the honor of paying an additional $20K.  But I wouldn't be able to honestly say in my confirmation hearings that I didn't know I owed it.  

And therein lies his real problem for confirmation.  He has to go in and admit he wilfully avoided taxes, which gives the Republicans a figleaf reason to vote against him, will give fraidy-cat democrats a reason for pause in their votes, and will potentially hurt the look of bipartisanship that the O's want to achieve in their confirmations.

It probably disqualifies him for Treasury, but I don't think it makes him a horrible person.

anyone even hinted as much. however, given that the rank-and-file in the IRS are subject to very stringent reporting/paying requirements, it would be just a tad hypocritical to have the secty. be someone unable to meet those basic obligations.

My confusion is that Mr. Geithner's earnings at the IMF apparently were not subject to witholding.

More confusing is that, in my guesstimate, the man's earnings were clearly sufficient to exceed the maximum total annual FICA payments for those years.  The witholding maxes out at a different top figure each year.  Per Samarak:
-1999   $72,600
-2000   $76,200
-2001   $80,400
-2002   $84,900
-2003   $87,000
-2004   $87,900
-2005   $90,000
-2006   $94,200
-2007   $97,500
-2008  $102,000
It seems that Geithner would have had more than $87,000 in wages subject to witholding in 2003, so there's some other factor involved with the "mistakes."

Wikipedia:

At the International Monetary Fund he was director of the Policy Development and Review Department (2001-2003).  In October 2003, he was named president of the Federal Reserve Bank of New York.[15] His salary in 2007 was $398,200.

Whoever paid him his wages in 2003 & 2004 should have taken out the FICA max.  If his IMF & Federal Reserve paychecks were not subject to FICA, then his failure to send it in may simply be a foolish mistake.

1. Note the second sentence.

"It's possible some of Mr. Geithner's problems stemmed from bad advice. In 2004, an accountant advised Mr. Geithner in writing that he did not owe employment taxes. An accountant who reviewed Mr. Geithner's 2001 tax return also didn't inform Mr. Geithner he owed taxes, according to an Obama aide familiar with the situation."

2. As someone mentioned, these were apparently the employer portion of self-employment taxes, and apparently organizations like the IMF do pay or withhold for self-employments taxes, even though they are owed. Note that the below protion of the IMF booklet doesn't mention the employer share of self-employement taxes.

"An IMF booklet on taxes, which Mr. Geithner told the Senate panel he received, instructed employees that "you pay the employee's share of U.S. Social Security taxes."

3. "Tax professionals noted that even trained preparers sometimes miss the subtleties involved in taxation of employees of international organizations."

Other bits of info:

A. With regard to his '01 and '02 tax returns, I believe the 3-year IRS statute of limitation had already run, at the time of the 2006 audit. Thus, in some respects, even though he hadn't paid those amounts, he really didn't owe them and the IRS had no way of collecting them.

B. 2006 IRS Press Release (note the 3rd para.):

"IRS Makes Settlement Offer to Certain Foreign Embassy Staff

IR-2006-180, Nov. 17, 2006

WASHINGTON -- The Internal Revenue Service today encouraged U.S.-based employees and former employees of foreign embassies, foreign consular offices and international organizations to participate in a one-time settlement initiative to resolve tax matters related to their employment.

The offer is only open to U.S. citizens, green-card holders and foreign employees with a U.S. tax obligation. Accredited diplomatic personnel are generally exempt from income taxes on their wages under international treaties or agreements.

The IRS estimates that as many as half of the employees subject to U.S. tax either fail to report their wages, claim deductions they are not entitled to, incorrectly establish SEP/IRA retirement plans, fail to pay self-employment tax or fail to file tax returns at all.

The IRS is offering a settlement initiative for these employees which will expire on February 20, 2007. In order to participate in the initiative the employees must submit amended or original tax returns for tax years 2003, 2004 and 2005 which properly reflect their income and expenses.

Failure to act now could mean facing a costly audit process in the future. Foreign embassy, consular office or international organization employees who fail to come forward may be subject to IRS audits and penalties which could cover more than just three years.

The IRS is offering a settlement initiative for these workers if they come forward between now and February 20, 2007."

Quoted below are some of the (unclear, in my view) certifications that he made (and some are trying to hand it for):

1. What does this mean? What's the difference between self-employed and employed obligation?

`I wish to apply for tax allowance of U.S. Federal and State income taxes and the difference between the "self-employed" and "employed" obligation of the U.S. Social Security tax which I will pay on my Fund income."

2. What does this mean? There's no reference to what tax allowance payments are. How does one calculate taxes on tax allowance payments? I would interpret this to mean that the taxpayer will pay income taxes on additional amounts received as tax allowance. When a taxpayer is "grossed up" for taxes or additional taxes, additional income taxes are owed on the gross up amount. Anyway, not very clear.