It started with a court battle over mayonnaise. In October 2014, Unilever, the multinational food titan, sued Hampton Creek, a small food-technology company, for false advertising. Unilever, which owns Hellmann’s and Best Foods mayonnaise, was contesting the name of Hampton Creek’s competing product, Just Mayo, a vegan substitute that uses yellow peas in place of eggs. Since the Food and Drug Administration defines mayonnaise as “egg yolk-containing,” Unilever argued that Just Mayo isn’t really mayo at all. The name, it claimed, was causing “serious, irreparable harm to Unilever.”

Much of the mainstream media covered the fight as a “weird war” between corporate competitors. (“Yep, It’s Mayo,” declared Inc. “No Eggs, No Mayo,” replied Entrepreneur.) But Ryan Noah Shapiro took the lawsuit seriously. A graduate student and animal-rights activist, Shapiro is a master at using the Freedom of Information Act—known as FOIA—to uncover public records that reveal how industry wields undue, and even illegal, influence over government agencies.

Shapiro suspected that Unilever was getting help in its war against Just Mayo. Egg manufacturers, for example, were also imperiled by vegan mayonnaise: Had they, too, been enlisted to fight Hampton Creek? Shapiro filed a series of FOIA requests to obtain the records of the American Egg Board, a government-funded trade group overseen by the U.S. Department of Agriculture. After months of haggling, the USDA released a batch of internal emails that Shapiro describes as “stunning.”

Industry groups like the egg board, which together received roughly $1 billion in federal funding last year, are supposed to use tax dollars to promote their own products—usually through advertising campaigns like the ones for beef (“It’s What’s for Dinner”) and pork (“The Other White Meat”). But the egg board, it turned out, was a chief architect of the smear campaign against Hampton Creek. Joanne Ivy, the board’s president, had emailed fellow board members, instructing them to consider Just Mayo’s success “a crisis and major threat to the future of the egg product business.” She solicited ideas to thwart Hampton Creek, and suggested pushing the FDA to declare Just Mayo’s label misleading. She also used a go-between PR firm to pressure Whole Foods to drop the product. (The grocery chain refused.) In one email, a member of the egg board joked that the trade group should arrange a Mafia hit on Joshua Tetrick, the CEO of Hampton Creek.

When the emails became public, Ivy resigned. Utah Senator Mike Lee called for a full USDA investigation. The records, he wrote, offer “compelling evidence” that leaders of the egg board “may have violated the federal laws and administrative regulations” that govern such tax-supported groups.