Shares of Wal-Mart Stores (WMT), the world's largest retailer, fell  Monday in response to a New York Times report alleging the company covered up a whistle-blower's complaints of widespread bribery at its Mexican subsidiary.

The stock was down almost 5% by noon. The stock, which had gained 4.5% this year, will no doubt fall further as more information emerges over the next few days. Though the Times' story has damaged Wal-Mart's reputation, investors shouldn't panic.

For one thing, the money involved -- $24 million, according to the Times -- seems small as Foreign Corrupt Practices Act (FCPA) cases go. For instance, Siemens AG (SI) was fined $800 million in 2008 after investigators uncovered evidence that the German conglomerate paid about $1.4 billion in bribes to foreign governments over a decade. 

That was the largest fine of its kind ever paid. A year later, Kellogg Brown & Root (KBR) and its former corporate parent Halliburton (HAL) pleaded guilty to charges of paying $182 million in bribes to officials in Nigeria. Kellogg Brown & Root agreed to a $402 million fine.

And BAE Systems (BA.L), the U.K. defense contractor, was fined $400 million after investigators found the company made "false statements about its Foreign Corrupt Practices Act compliance program."

If the money involved in the Wal-Mart case proves to be more than reported so far, the company, which has more than $6 billion in cash on its books, could still write a check to the government to pay a fine without breaking a sweat.

Unfortunately, however, it will take more than just money to repair Wal-Mart's tattered reputation.

Probably the most disturbing part of the Times story lies in the allegations involving current Wal-Mart top executives and board members. According to the report, current CEO Mike Duke, who headed Wal-Mart International at the time of the payoffs, did nothing to stop them. Former CEO and current board member H. Lee Scott allegedly "rebuked internal investigators for being overly aggressive." And vice chairman Eduardo Castro-Wright, who at one point was the head of Wal-Mart de Mexico, was described by the Times as the "driving force behind systemic bribery in Mexico." 

Duke could argue that he didn't remember the email he received several years ago from a lawyer saying, "You'll want to read this," referring to detailed allegations of rampant bribery from a former Wal-Mart executive. He is a busy man who reads lots of things. Scott could make a similar argument. Castro-Wright may claim the payoffs were the work of rogue employees going out on their own.

Even if they are in the clear legally, the question of whether the executives met their moral responsibilities is another issue. Wal-Mart faces the dilemma of proving to its more than 2 million workers around the world that everyone has to follow the same rules. The company has said it will "not tolerate noncompliance with FCPA anywhere or at any level of the company."

If Duke, Scott and Castro-Wright are forced to leave Wal-Mart -- a big if -- the retailer will have little difficulty replacing them. The average U.S. Wal-Mart shopper probably could not care less about whether the company bribes foreign governments.

The only winners in this scandal are the shareholders who are buying Wal-Mart stock at a discount.

Jonathan Berr is long Wal-Mart. Follow  him on Twitter @jdberr.