On June 6, 2016 , Majority Leader Mitch McConnell joined his wife, Elaine Chao, now the U.S. secretary of transportation, at a ceremony on the Harvard Business School campus to dedicate a new building emblazoned with the Chao family name. Funded by a $40 million gift from the Chao family and its foundation, the building would serve as a new hub for Harvard’s Executive Education program. But the family’s generosity appears to have come at the expense of taxpayers — the money, it turns out, would already have been in the public treasury had it not been sheltered from the government in complex offshore tax havens.

Over a period of five years, millions of dollars were quietly funneled to a Chao family foundation via two offshore firms that list a New York address but are not incorporated anywhere in the United States. Two entities with the same names, however, are incorporated in the Marshall Islands, known as one of the world’s most secretive offshore havens for firms seeking to avoid taxes and a preferred foreign locale for the Foremost Group, the Chao family’s New York-based shipping business. The Foremost Group and a spokesperson for the Department of Transportation declined to comment on where the two donating firms are incorporated.

Chao, notably, has been a key voice in promoting the Trump administration economic policies, including the historic rewrite of the tax code — a legislative accomplishment that is likely the pinnacle of McConnell’s congressional career. The reform shifted the corporate tax code to a territorial system, a move highly expected to reward firms that funnel earnings through offshore tax havens, such as the Cayman Islands or the Marshall Islands. Speaking at the Davos World Economic Forum’s annual meeting in January, Chao called Trump’s “America first” policies “the affirmation of American exceptionalism.” Critics, she noted, “who don’t want to listen to him can leave.”

The connection between the offshore accounts and the donation to the Chao family foundation were found through a search of the Paradise Papers — a trove of more than 13 million leaked documents from tax havens around the world obtained by German newspaper Süddeutsche Zeitung and shared by the International Consortium of Investigative Journalists with reporting partners around the world.

The documents reviewed by The Intercept highlight the extent to which Chao’s family shipping business has made use of offshore jurisdictions. Chao also appears connected to her family’s offshore firms in ways that have not been reported. Both a Chao family foundation website and her LinkedIn page list Chao as having chaired the foundation associated with the Harvard gift.

In response to a request for comment, Marianne McInerney, a spokesperson at the Transportation Department, said in an email that Chao was a volunteer chair for the foundation between 2013 and 2014 and that she “had no day-to-day responsibilities and received no compensation.” McInerney also said Chao has no affiliation with the family shipping business, the Foremost Group. “The Secretary,” she said, “complies with all applicable ethics requirements.”

The Foremost Group did not respond to emails and calls requesting comment.

McConnell married Chao, the daughter of shipping magnate James Si-Cheng Chao, in 1993. James Chao fled the civil war in China to arrive in Taiwan, and shortly thereafter immigrated to the United States, where he began his building an international shipping business. Thanks to the Foremost Group, McConnell and Elaine Chao, one of Washington’s most politically powerful couples, are also estimated to be millionaires many times over. Though Chao has never played a leadership role in the company, her father gave the couple a gift of between $5 million and $25 million in 2008, according to Politico. McConnell’s net worth was about $26.7 million in 2016, according to a Center for Responsive Politics estimate.

The Chao family’s use of offshore structures came to light in 2014 when The Nation reported that the family business had routed ownership of its cargo ships through a series of opaque registrations in Liberia and the Marshall Islands. The Foremost Group fleet consists primarily of dry-bulk cargo ships carrying commodities, including coal, to ports around the world.

In 2016, ProPublica reported that the Foremost Group had registered a total of 17 cargo ships offshore, mostly via subsidiaries registered in the Marshall Islands. This raised concerns that Chao may face a conflict of interest because her job as transportation secretary involves overseeing the Maritime Administration, which encourages shipping firms in certain sectors to register their vessels in the United States.

“There is no conflict of interest,” said McInerney. She said the department doesn’t regulate foreign-flagged ships, and regulations determine which trades require ships to fly a U.S. flag.