More than a dozen National Basketball Association stars may soon be facing off against a formidable new opponent: Congress. Some Republicans are demanding that NBA players sever endorsement contracts with Chinese sportswear firms Anta and Li-Ning whose cotton supply chains are implicated in forced labor in China’s Xinjiang province. The Trump administration banned imports of Xinjiang cotton and products containing it in January.

“Americans can’t and shouldn’t conduct business with companies and players that profit through human slavery,” Rep. Scott Perry (R-Penn.) told POLITICO. “And that includes NBA players — they can’t sign endorsement deals and benefit off slave labor.”

Scott isn’t alone in his scrutiny of NBA players with links to Chinese sportswear firms whose supply chains are tainted by forced labor allegations. The bipartisan Congressional-Executive Commission on China is also probing NBA players’ commercial relationships with Anta, Li-Ning and a third Chinese sport wear company, Peak, due to their reliance on Xinjiang cotton for their products. And the Senate’s July 15 passage of the Uyghur Forced Labor Prevention Act will likely only intensify sensitivity in Congress to firms with supply chains linked to forced labor in Xinjiang.