Sen. Josh Hawley (R-MO) sent a letter to Attorney General William Barr on Tuesday, urging him to open a criminal antitrust investigation against Amazon for stifling competition.

According to a Wall Street Journal report released last week, Amazon used data and sales to develop its own, competing products against other businesses competing on its Amazon marketplace. The Journal wrote:

The online retailing giant has long asserted, including to Congress, that when it makes and sells its own products, it doesn’t use information it collects from the site’s individual third-party sellers—data those sellers view as proprietary.

Yet interviews with more than 20 former employees of Amazon’s private-label business and documents reviewed by The Wall Street Journal reveal that employees did just that. Such information can help Amazon decide how to price an item, which features to copy or whether to enter a product segment based on its earning potential, according to people familiar with the practice, including a current employee and some former employees who participated in it. In one instance, Amazon employees accessed documents and data about a bestselling car-trunk organizer sold by a third-party vendor. The information included total sales, how much the vendor paid Amazon for marketing and shipping, and how much Amazon made on each sale. Amazon’s private-label arm later introduced its own car-trunk organizers. Hawley contended that Amazon’s business practices serve as an existential threat to small businesses competing against Amazon on the Internet giant’s marketplace. “These practices are alarming for America’s small businesses even under ordinary circumstances. But at a time when most small retail businesses must rely on Amazon because of coronavirus-related shutdowns, predatory data practices threaten these businesses’ very existence,” the Missouri senator wrote.

“Abusing one’s position as a marketplace platform to create copycat products always is bad, but it is especially concerning now,” Hawley added. “Thousands of small businesses have been forced to suspend in-store retail and instead rely on Amazon because of shutdowns related to the coronavirus pandemic. Amazon’s reported data practices are an existential threat that may prevent these businesses from ever recovering.”

Hawley noted that the European Union already opened an investigation into Amazon using data in an anticompetitive fashion against third-party businesses.

“In the light of the enormous evidence already gathered, I ask that you look into this issue and open a criminal antitrust investigation of Amazon,” Hawley wrote.