Costco Wholesale (COST) is accused of supporting forced labor in Thailand by selling farmed shrimp from that country, where human trafficking is widespread, and allegedly misleading consumers about it.
The purpose of the lawsuit filed Wednesday in San Francisco federal court is the "education of consumers to make sure they are not being served slavery on a dinner plate," Derek Howard, an attorney in Mill Valley, California, who is serving as co-counsel in the case, told CBS MoneyWatch.
The suit, filed on behalf of a California resident, cites state laws that ban corporations from making false claims about illegal behavior in the supply chain.
"Human suffering cannot be ignored to enhance a company's economic bottom line," plaintiffs' attorney Niall McCarthy, of Cotchette, Pitre & McCarthy, said in a statement. "California consumers are unknowingly supporting slave labor."
In a statement, Costco spokesman Bob Nelson said: "Costco Wholesale has been working with and will continue to work with various stakeholders (including the Thai government, other retailers, and Thai industry) to address the issues that have surfaced. In the meantime, all of our customers know that if they are dissatisfied with any purchase from Costco Wholesale they can return the item for a full refund."
Thailand is the world's third-largest exporter of seafood, with annual sales of roughly $7.3 billion a year, according to the complaint. The industry, which extends into international waters around Indonesia, involves more than 650,000 people, mainly migrants who enter Thailand looking for work or who are taken there against their will, the lawyers claim.
Costco's relationship with a Thai shrimp producer named in the suit contradicts the retailer's public statements about slavery in its supply chain, according to the complaint.
The U.S. State Department last month blacklisted Thailand for a second consecutive year for not doing enough to fight modern-day slavery. A July 28 report from the department labeled labor abuses in the Southeast Asian country's seafood sector persistent, abusive and largely ignored by the Thai government.
"Some men remain at sea for several years, are paid very little or irregularly, work as much as 18 to 20 hours per day for seven days a week, or are threatened and physically beaten," the report said.
Thailand, Iran, Syria and Zimbabwe are among 23 nations that drew the lowest ranking in the yearly U.S. assessment of how 188 governments around the world are battling the flesh trade and other types of exploitative labor.
The lawsuit also names as a defendant the U.S. distributor of the prawns, Columbia, Maryland-based CP Food Products, and its Thailand-based parent company, Charoen Pokphand Foods Public Co. CBS MoneyWatch requests for comment from the companies were not returned.