Non-lethal weapon may spark controversy.

NO SPEAKERS elicited more questions from the audience at a recent directed energy conference than Stephanie Miller, a researcher at the Air Force Research Laboratory's human effects directorate.

The attendees, composed of military and industry directed energy experts, peppered her with questions about the active denial system, a non-lethal weapon that employs microwave millimeter technology to make human targets recoil from attack by causing debilitating pain.

Can the weapon cause cancer or severe burns? What happens to intoxicated individuals who can't step out of the way? Can it stop a suicide bomber? Does it cause heart attacks? Has it been tested on tortoises and other animals?

The intense curiosity from experts in the field is perhaps a harbinger of things to come once the public learns of the weapon, which Pentagon officials have indicated may be deployed in Iraq within a year.

As for the animal question, Miller didn't crack a smile or appear surprised. The effect of the weapon on tortoises is a serious consideration, she pointed out. Some may fall under the Endangered Species Act, and their well-being must be taken into account when tests in the New Mexico desert are conducted.

Concerning the weapon's effects on humans, Miller said more than 500 military personnel have volunteered to stand in its path totaling more than 9,000 exposures.

The energy causes water molecules at one-third of a millimeter below the skin's surface to vibrate, thus creating heat picked up by nerve endings. The sensation has been described as a bee sting all over the body. Miller said test subjects have a reflexive reaction to the pain, which causes them to immediately move out of its path. "Mind over matter doesn't work particularly well in this case," she said of potential suicide bombers.

For those who are incapacitated and can't move away, the weapons will be set at a timed exposure, Miller said. No test subjects have ever been burned, and limits for eye safety have been tested.

"We know the safety margins for skin and eye injuries," she said.

The directorate has not tested for heart attacks, she said. The weapon does not react to the body that way, she insisted. Since the waves only penetrate one-third below the surface of the skin, they do not interact with internal organs. While victims of the Taser, another non-lethal tool used widely by law enforcement, have suffered heart failure, there is no evidence directly linking the intense pain to the weapon. Taser victims may have had drugs in their systems or other mitigating factors, she said.

As for cancer, the weapon uses non-ionizing radiation that does not have the ability to initiate the disease, Miller said.

Marine Corps Col. David Karcher, commander of the joint non-lethal weapons directorate, said Defense Department public affairs personnel have been ordered to take a "passive stance" on the active denial system, meaning they will answer questions on the weapon when asked, but are not actively touting its abilities.

The directorate nevertheless must brace itself for such questions from the public, and have clear answers on what the weapon can and can't do, Karcher added. Opponents of non-lethal weapons may submit Freedom of Information Act requests seeking the results of big-effects testing, and could start a campaign to shut programs down before they reach the battlefield.

"And that may kill the program," he warned.