The Swiss bank also hired Mr. Wray, then a partner at King & Spalding in Washington who had served as the head of the Justice Department’s criminal division and oversaw the Enron task force. (Mr. Wray became the director of the F.B.I. three years after he negotiated the final plea deal for Credit Suisse.)
“It is a mystery to me why the U.S. government didn’t require as part of the agreement that the bank cough up some of the names of the U.S. clients with secret Swiss bank accounts,” Carl Levin, then a Michigan senator leading an investigation into offshore tax avoidance, said after the 2014 plea agreement.
In the interview, Mr. Neiman, the whistle-blower’s lawyer, said that in July 2014, after the plea deal was signed and as Credit Suisse awaited its final sentencing, he told officials at the tax division of the Justice Department and federal prosecutors who had worked on the case that his client had information that the bank had continued to cloak money held by some U.S. account holders. He gave them one name in particular — Dan Horsky, the retired business professor, who lived in Rochester, N.Y.
The tip checked out. The following year, federal agents arrested Mr. Horsky, who had amassed a $200 million fortune and hidden it with the help of Credit Suisse bankers using offshore shell companies, court documents show. The arrangement lasted for several months after the bank signed its plea deal.
It is unclear why the Justice Department did not notify the court and change the terms of its settlement with Credit Suisse based on the information from the whistle-blower — either before Credit Suisse’s final sentencing or after Mr. Horsky’s case became public. At the sentencing, lawyers for both sides told the court that they had no information to add that would affect the agreement.
Officials who would have had authority to make the decision to review the Credit Suisse case for possible breaches in 2014 and 2015 — including James Cole, who was then the deputy attorney general, and Dana Boente, the U.S. attorney in the Eastern District of Virginia — did not respond to requests for comment.
In 2015, Mr. Horsky pleaded guilty to defrauding the U.S. government and said that he would cooperate with prosecutors. In 2017, he was sentenced to seven months in prison. Some details of his sentencing are sealed, and a federal judge denied a request by Bloomberg News to unseal it. The judge said he denied the request after consulting with the Justice Department and Mr. Horsky’s lawyers.
Mr. Neiman’s client could be richly rewarded if prosecutors move to impose more fines on Credit Suisse. Under an I.R.S. rule, whistle blowers can get as much as 30 percent of the amount of any additional money the government gets. And, Mr. Neiman said, the whistle blower has more names of American account-holders beyond Mr. Horsky’s, although he wouldn’t say how many.