The director of the Office of Government Ethics, the nonpartisan agency charged with vetting the financial disclosures of cabinet nominees for potential conflicts of interest, sent an extraordinary letter to Senate Democratic leaders late last week. Never in the four-decade history of the agency, he wrote, have ethics officials felt such “undue pressure ... to rush through these important reviews,” leaving “some of the nominees with potentially unknown or unresolved ethics issues shortly before their scheduled hearings.”

As the Senate races forward with confirmation hearings this week, the spottiest disclosures have come from wealthy private-sector nominees with no governing experience and many potential conflicts. In other words, the people most in need of a complete ethics review.

Exhibit A is Betsy DeVos, a billionaire and education lobbyist who is President-elect Donald Trump’s pick for education secretary. Ms. DeVos’s finances are a tangle that could take weeks to investigate. Despite that, Republicans had set her confirmation hearing for Wednesday. But late Monday night, they pushed it back to next Tuesday.

People who have seen her financial disclosures so far say that Ms. DeVos and her husband, Dick DeVos, have investments in some 250 companies registered to a single Grand Rapids, Mich., address, entities whose investments could take weeks for the ethics office to research. Already, though, there are reports that the DeVoses are indirect investors in Social Finance Inc., a private company that refinances student loans. Private lenders like Social Finance are banned from most of the direct student lending market; their lobbyists have already written to the Trump transition team pitching to change that. That’s only one potential conflict. What if her family has holdings in educational technology or for-profit colleges? Given time, the ethics office will learn this, and reach an agreement with Ms. DeVos to sell off assets that could pose a conflict.