An expert testified Tuesday in an Air Force court-martial proceeding that an anthrax vaccine used by the military was never properly tested or licensed.

Dr. Meryl Nass of Freeport, Maine, a member of several hospital boards who has conducted studies on the effects of anthrax on humans, testified in proceedings at Keesler Air Force Base for Capt. John Buck.

Buck, a 32-year-old emergency room physician, is accused of disobeying an order to take the vaccine before deployment to the Middle East last October.

In the pretrial session, Buck is asking Lt. Col. Mark Allred, the presiding judge, to dismiss the charge. Buck contends the order was unlawful because it's an experimental drug requiring a soldier's consent before it can be administered.

Allred may rule on this key aspect of the case Wednesday. Depending on his findings, he may dismiss the charge or rule that the order was lawful. Allred could also leave it up to a military jury to decide if the order was lawful.

Testimony on Tuesday centered on Nass, the sole witness to appear so far.

Nass said the vaccine used in government programs was only thoroughly tested on animals. She said there was no data to show whether the drug was effective and safe for humans.

The military insists the vaccine is the best weapon against biological attacks. Pressure mounted to immunize soldiers to biological agents in the wake of the Gulf War.

"This is for the critical health and protection of our troops. It's considered our first line of defense against anthrax biological warfare," Capt. Jim Winner, a spokesman for the prosecution, said.

Frank Spinner, a retired Air Force lieutenant colonel and lead defense lawyer, said he had documents to show the government was aware of problems with the vaccine and had attempted to develop a different form to meet federal requirements.

Questions have been raised about whether the anthrax vaccine licensed in 1970 ever met federal Food and Drug Administration standards. Nass said that was because there were no clinical studies done on humans as required by FDA.

"I think they've made it very clear that mass inoculation with this vaccine is not recommended," Nass said regarding an FDA document.

"I don't hold that there is some grand conspiracy on the part of the Department of Defense," Spinner said.

"But sometimes the word on the street doesn't reach up," he added. "I also know that generals don't always listen."

However, Belinda Bazinet, a Keesler Base spokeswoman, said several independent panels have reviewed the vaccine and found it safe and efficient.

Anthrax is a disease that typically afflicts animals, especially sheep and cattle. Dry anthrax spores, which can be put into weapons, can cause death in humans if inhaled.

Buck, a Pascagoula native, is a key figure in the resistance to the mandatory anthrax program. The program was started in 1998 out of fear of biological warfare against American diplomats and soldiers.

The resistance and allegations against the program have prompted legislators to review it.

On Tuesday, Rep. Christopher Shays, R-Conn., issued a statement in support of Buck, saying, "No allegedly lawful military order should require a doctor to violate his Hippocratic oath."

During later testimony Tuesday, Nass said there was an absence of data to show the anthrax vaccine does not cause cancer or fetal harm.

She said up to 100 women had contacted her about possible side affects from the inoculation, including birth defects.

Military lawyers, who had challenged Nass' qualifications as an expert witness, planned to question her later in the proceedings. They said Tuesday no decision had been made on whether they would call their own witness.

Buck and a former Air Force major filed suit May 2 against FDA and the Defense Department in U.S. District Court in Washington seeking to end the program.

If the class action lawsuit is successful, more than 200 soldiers discharged or disciplined for refusing to take the vaccine could have their records expunged.

In the court-martial proceedings against Buck, the prosecution seems to want to steer the trial away from debating whether the anthrax policy is hazardous to military personnel.

Winner said the focus should be on whether Buck disobeyed an order by Col. Richard Griffith in mid-October.

Allred refused a motion by the defense to bring a second witness, Kwai-Cheun Chan, to the stand.

Chan worked on a recent General Accounting Office report that was critical of a worldwide State Department program to get military and diplomatic personnel and their families to voluntarily take anthrax vaccines.

Buck is expected to plead innocent after the preliminary pretrial motions have been heard.

If the judge rules to continue with the court-martial, a panel of at least five officers will have to be seated as a military jury.

A two-thirds vote by the jury is needed for a guilty verdict.