Wal-Mart has taken the latest in a  long series of steps to make itself look good by imposing burdens on  its suppliers. The mammoth retailer, which is thriving amid the  recession, recently announced plans to require its more than 100,000  suppliers to provide information about their operations that would  form the basis of a product sustainability index.

Rating products is a good idea. It’s already being done by various  non-profit organizations that bring independence and legitimacy to the  process. Wal-Mart, by contrast, brings a lot of negative baggage.

In recent years, Wal-Mart has used a purported commitment to  environmental responsibility to draw attention away from its abysmal  record with regard to labor relations, wage and hour regulations, and  employment discrimination laws. It also wants us to forget its  scandalous tax avoidance policies and its disastrous impact on small  competitors.

The idea that a company with a business model based on automobile- dependent customers and exploitative supplier factories on the other  side of the globe can be considered sustainable should be dismissed  out of hand. Yet Wal-Mart is skilled at greenwashing and is, alas,  being taken seriously by many observers who should know better.