Sweeping stun guns to target crowds
19:00 16 June 04
Exclusive from New Scientist Print Edition.
Weapons that can incapacitate crowds of people by sweeping a lightning-like
beam of electricity across them are being readied for sale to military and
police forces in the US and Europe.
At present, commercial stun guns target one person at a time, and work only
at close quarters. The new breed of non-lethal weapons can be used on many
people at once and operate over far greater distances.
But human rights groups are appalled by the fact that no independent safety
tests have been carried out, and by their potential for indiscriminate use.
Taser success rates by distance
The weapons are designed to address the perceived shortcomings of the Taser,
the electric-shock gun already used by 4000 police departments in the US and
undergoing trials with some police forces in the UK.
It hits the victim with two darts that trail current-carrying wires, which
limit its range to a maximum of seven metres (see graphic). As a single
shot, short-range weapon, the Taser is of little use in crowd control. And
Tasers have no effect on vehicles.
These limitations are beginning to be overcome. Engineers working for the US
Department of Defense's research division, DARPA, and defence companies in
Europe have been working out how to create an electrically conductive path
between a gun and a target without using wires.
A weapon under development by Rheinmetall, based in Dorf, Germany, creates a
conducting channel by using a small explosive charge to squirt a stream of
tiny conductive fibres through the air at the victim (New Scientist print
edition, 24 May 2003).
Meanwhile, Xtreme Alternative Defense Systems (XADS), based in Anderson,
Indiana, will be one of the first companies to market another type of
wireless weapon. Instead of using fibres, the 00 Close Quarters Shock
Rifle projects an ionised gas, or plasma, towards the target, producing a
conducting channel. It will also interfere with electronic ignition systems
and stop vehicles.
"We will be able to fire a stream of electricity like water out of a hose at
one or many targets in a single sweep," claims XADS president Peter Bitar.
The gun has been designed for the US Marine Corps to use for crowd control
and security purposes and is due out in 2005. It is based on early, unwieldy
technology and has a range of only three metres, but an operator can
debilitate multiple targets by sweeping it across them for "as long as there
is an input power source," says Bitar.
XADS is also planning a more advanced weapon which it hopes will have a
range of 100 metres or more. Instead of firing ionised gas, it will probably
use a powerful laser to ionise the air itself. The idea has been around for
decades, says LaVerne Schlie, a laser expert at the US Air Force Research
Lab in Kirtland, New Mexico. It has only become practical with advances in
high-power solid-state lasers.
"Before, it took a laser about the size of two trucks," says Schlie. "Now we
can do it with something that fits on a tabletop."
The laser pulse must be very intense, but can be brief. So the makers of the
weapons plan to use a UV laser to fire a 5-joule pulse lasting just 0.4
picoseconds - equating to a momentary power of more than 10 million
This intense pulse - which is said not to harm the eyes - ionises the air,
producing long, thread-like filaments of glowing plasma that can be
sustained by repeating the pulse every few milliseconds. This plasma channel
is then used to deliver a shock to the victims similar to a Taser's
50,000-volt, 26-watt shock.
Instrument of torture
HSV Technologies of San Diego, California is also working on stun and
vehicle-stopping shock weapons with ranges of over 100 metres. And another
company, Ionatron of Tuscon, Arizona, is due to supply a prototype wireless
vehicle-mounted weapon to the US Department of Defense by the end of 2004.
But the advent of wireless stun weapons has horrified human rights groups.
Robin Coupland of the Red Cross says they risk becoming a new instrument of
torture. And Brian Wood of Amnesty International says the long-range stun
guns could "inflict pain and other suffering on innocent bystanders".
And there are safety concerns. Of the 30,000 times US police officers have
fired Tasers, in 40 instances people stunned by them later died. The deaths
have been attributed to factors such as overdoses of drugs and alcohol, or
fighting with officers, rather than the electric shock.
In a statement, Taser International chief Rick Smith said: "In every single
case the medical examiner has attributed the direct cause of death to causes
other than the Taser." Amnesty is not convinced, however, and wants an
independent study of the effects of all existing and emerging electric-shock