Here’s a sure way to lose half your cooperation credit in a federal investigation: Let your in-house counsel advise employees not to cooperate with U.S. prosecutors.

That’s what Swiss government-owned Zürcher Kantonalbank did, and now it owes the United States $98.5 million in restitution, forfeiture and fines. The Zurich-area institution is the largest canton (township) bank and the fourth-largest bank in Switzerland.