In the United States, two Air Force officers are suing the Department of Defense over its use of the anthrax vaccine. Air Force Capt. John Buck, a doctor, and former Air Force major Sonnie Bates filed a lawsuit against the Department of Defense arguing that the military should not inoculate troops with a vaccine that has not received final approval from the Food and Drug Administration. According to the men's lawyer, John J. Michels Jr., the Department of Defense should call the medication an experimental drug, which would permit members of the military to refuse to take it if they wanted. Following a two-hour hearing, U.S. District Judge Reggie B. Walton stated that he was hesitant for the court to issue an order concerning a medical issue, as opposed to medical experts. The U.S. military started immunizing troops against anthrax in 1998, and since then over half a million active-duty and reserve troops have received the shot. The vaccination campaign was halted in 2001 because of a shortfall in supplies, but a lawyer for the Justice Department said the vaccinations will eventually resume once supplies of the vaccine become available. In the past few years, approximately 500 members of the military have refused to take the anthrax vaccine, citing safety and health concerns.