This post is by Erika Kelton at Forbes.com.

Whistle-blowers are responsible for some of the federal government’s biggest recoveries in fraud cases. The Obama administration recently trumpeted that more than $21 billion has been recovered as a result of “qui tam” (whistle-blower) cases brought under the False Claims Act -- and that total doesn’t include the many billions more recovered as a result of criminal fines related to those civil cases. Nor does it include the tens of billions saved by the powerful deterrent effects of that robust whistle-blower program.

With results like that, why would the Internal Revenue Service resist the opportunity to collect billions in tax revenues from scofflaws with the help of whistle-blowers who provide detailed information about major tax frauds and other tax law violations? It’s puzzling, particularly at a time when the federal Treasury needs every dollar it can get.

Congress thought it was a great idea to encourage whistle-blowers to inform the IRS about significant tax frauds and other tax law violations by offering them an award from the recoveries and enacted a law to do that in December 2006. But in the past five years, the IRS has given only one known whistle-blower a reward under the program. At the same time, it is sitting on a mountain of whistle-blower claims.

The problem with the IRS whistle-blower program isn’t the 2006 law or the quality of whistle-blower information that the IRS is receiving. The IRS Whistleblower Office reports that it has received dozens of whistle-blower submissions concerning matters involving tax losses greater than $100 million and thousands involving tax underpayments that exceed $2 million. The real problems are the IRS itself and institutional resistance to whistle-blowers within the IRS, which is hobbling the whistle-blower program and draining its enormous promise. (Post continues after video.)

The anti-whistle-blower attitude was succinctly expressed by former IRS Chief Counsel Donald Korb shortly after he left the IRS and joined a white-collar law firm that defends companies against the IRS. In a 2010 interview with the publication Tax Notes, he said:

The new whistle-blower provisions Congress enacted a couple of years ago have the potential to be a real disaster for the tax system. I believe that it is unseemly in this country to encourage people to turn in their neighbors and employers to the IRS, as contemplated by this particular program. The IRS didn’t ask for these rules; they were forced on it by the Congress.

Such comments are surprising coming from a former government official who was charged with implementing the laws of this country. But they also reflect a mindset at the IRS that for some has gone unchanged despite the substantial and time-tested success of whistle-blower programs.

Congress made it very clear that it wanted the IRS to encourage whistle-blowers to help recover taxes the government is owed. From my vantage point, the IRS Whistleblower Office does its best but faces stiff headwinds from the IRS Office of Chief Counsel, which has stymied the whistle-blower program by interpreting the 2006 law in ways that discourage whistle-blowers and undermine the program’s potential for success.

The list of problematic guidance from the OCC is long and includes rules that have:

• Narrowed the sources of recovery that are the basis of whistle-blower awards.
• Imposed unprecedented withholding requirements on whistle-blower awards.
• Created roadblocks to IRS interactions with whistle-blowers, such as the 2008 "one-bite" rule (now relaxed) that limited receipt of information to an initial meeting.
• Defined "planners and initiators" of the tax scheme -- who by law receive only a reduced award (if any) -- in a manner that could block employees whose involvement is far removed from the true architects of a scheme from receiving a reward.

Whistle-blowers and their lawyers also are frustrated that the IRS has created a black hole for whistle-blower claims, so they get little or no information about the claims’ status.

Perhaps the paramount frustration, however, is due to the apparent unwillingness of the IRS to take advantage of whistle-blowers' expertise and allow them to assist the IRS in certain, limited circumstances. This assistance clearly is contemplated by the 2006 law and could be allowed without violating confidentiality restrictions through the use of special confidentiality agreements known as 6103(n) contracts. Why the IRS has ignored resources that it is free to tap is a mystery, especially as the agency suffers through staffing cutbacks.

Contrast the IRS attitude with that of the Securities and Exchange Commission, which welcomes the help of whistle-blowers under the SEC’s 19-month-old whistle-blower program, and the Justice Department, which has a long-standing public-private partnership with whistle-blowers to combat frauds against the government through "qui tam" lawsuits brought under the False Claims Act. An SEC enforcement official told Congress last year that high-quality whistle-blower information had saved the SEC six to 12 months of investigative time on a matter the SEC learned about only from that insider. The IRS could benefit in the same way from whistle-blowers.

Potential whistle-blowers, particularly those in the executive suite, are well aware that only one known award has been made under the program in five years. Seeing that chances of a reward are hampered by the IRS’s attitude, a painfully slow bureaucracy and an attitude that shuns needed help, whistle-blowers are thinking twice about risking their livelihoods to come forward. The statistics in the IRS Whistleblower Office’s 2010 report to Congress confirm that there has been a drop in the number of whistle-blower submissions.

Congress gave the IRS the tools to establish a robust whistle-blower program that could help close the $450 billion annual gap between what is owed in taxes and what is paid. Instead, the IRS is using bureaucratic maneuvers to quietly sideline the whistle-blower program. The ultimate loss will be to taxpayers and the federal Treasury, which could be recovering tens of billions that are sorely needed.

More from Forbes.com and MSN Money:

• 'Aggressive' tax returns can mean fraud
• IRS claims nearly $1 billion owed to taxpayers for 2008
• 12 tax scams to avoid like the plague
• IRS owes taxpayers $1 billion for 2008
• Tea Partyers, IRS spar over tax status
• Are budget cuts crippling IRS?