Last week's suicide by a government biodefense researcher who had been linked to the mailing of anthrax-laced letters in 2001 has raised thorny questions about whether the benefits of biodefense research outweigh the risks. Researcher Bruce Ivins had reportedly been informed by the FBI that he was about to be indicted for murder in the incident that killed five people and sent 17 more to the hospital. Some observers point out that biodefense research has vastly increased since the terrorist attacks of 2001, and raise the question: