Steven Hatfill is a virologist and bio-weapons expert. The Department of Justice identified the former government scientist as a "person of interest" in its investigation of the 2001 anthrax attacks but has not sought charges. FBI raids on his home were well attended by journalists. By implication, several news outlets and millions of Americans have speculated that Hatfill is the likeliest suspect for the anthrax attacks.

Hatfill has maintained that he is innocent and is suing the government for compensation for the damage he claims has been inflicted on his professional reputation and employment prospects. His lawyer, Victor M. Glasberg, stated:

'Steve's life has been devastated by a drumbeat of innuendo, implication and speculation. We have a frightening public attack on an individual who, guilty or not, should not be exposed to this type of public opprobrium based on speculation.

Steven Hatfill was born in St. Louis, Missouri, and attended Southwestern College in Winfield, Kansas. Here he studied biology. Later he worked as a medical missionary in Kapanga, Zaire under his mentor Dr. Glenn Eschtruth. Hatfill would later marry Dr. Eschtruth's daughter, Caroline. The couple divorced and Hatfill settled in Rhodesia to study medicine at the Godfrey Huggins Medical School.

He later worked at USAMRIID, where he may have had access to anthrax.