Starbucks Corp.'s (NASDAQ: SBUX) reputation as one of the good guys of corporate America may be in jeopardy. The National Labor Relations Board has accused the coffee company of illegal anti-union activity at a store in Michigan, the second such charge it has received in the past month. The company is also on trial in New York on charges of similar union-busting efforts involving the International Workers of the World.

Business Week takes a look at the labor woes circling around Starbucks, and even makes a comparison to Wal-Mart (NYSE: WMT), America's bad boy of labor relations.

And that may be the most damaging thing to come out of this. Starbucks' wild popularity is as much a function of its atmosphere and reputation as it is a function of the quality of its products. Will people want to patronize a store when the newspapers sold there are reporting on labor violations?

Wal-Mart's sales may be suffering from its reputation but, based on the demographic Starbucks appeals to, I would expect that this publicity could be far more damaging.

Starbucks shareholders will want to monitor these stories closely. While the legal costs to the company may not be material, the intangible damage could be very material.