Under the settlement, the government also agreed to quickly release children from detention. To get around Flores and detain adults who were traveling with children, the Trump administration separated families at the border. When that policy incited immense backlash, the administration produced regulations to replace Flores, but a federal judge ultimately rejected that effort.

Despite the Trump administration’s antipathy to the settlement, it nonetheless abided by Flores’s food and water requirements. Inspector general reports in 2018, 2019 and 2020 found that all Border Patrol facilities that investigators visited had baby formula available. A news release from Customs and Border Protection in 2019 also noted that facilities provided formula.

Congress itself has explicitly cited infant formula in funding legislation for Customs and Border Protection. For example, lawmakers gave the agency $40.2 million in 2019 for “commodities such as food, infant formula and diapers.”

Like most government agencies, Customs and Border Protection purchases supplies in bulk, typically months or years in advance. For example, the agency awarded a multimillion-dollar contract to a food distributor in 2015 for five years’ worth of meals for detained migrant children in the Rio Grande Valley sector.

Customs and Border Protection did not respond to questions about its procurement process for formula. But the agency said in a statement that “ensuring migrants, including children and infants, in our custody have their basic needs met is in line with this administration’s commitment to ensuring safe, orderly and humane processes at our border.” The agency, the statement said, “complies with all applicable regulations for the purchase of products used in C.B.P. facilities.”

Steven L. Schooner, a professor of government procurement law at George Washington University, was skeptical that the agency’s purchases had any effect on the current supply of baby formula.

“I’m extremely confident that any volume of formula that D.H.S./C.B.P. buys is statistically the equivalent of zero in terms of market share,” he wrote in an email, referring to the agency and the Department of Homeland Security. “Indeed, I’d be stunned if the government bought any significant volume.”