The stakes could not have been higher. David Ard, former regional sales manager for Stryker Corp.’s biotechnology unit, faced charges of conspiracy and wire fraud related to the marketing of a bone growth product that hadn’t received U.S. Food and Drug Administration approval. He turned to Brent Gurney and Miranda Hooker of Wilmer Cutler Pickering Hale and Dorr.

Gurney, a partner, and Hooker, a counsel, assessed the case against their client as particularly weak, so they adopted a simple strategy: They refused to communicate with federal prosecutors. “The best defense often means staying silent,” Gurney said. “The U.S. attorney’s office never had any idea what we were going to argue. We kept it that way until the trial began.”