The day Sir Lancelot lost to a beanbag

Picture the scene. A 6ft 2in ex-Marine charges out of an apartment building towards a group of armed police officers. The giant, a Californian dressed in armour and chain mail, is whirling a huge medieval sword like Excalibur over his head.

The policeman first in line takes aim for the heart, with what looks like a rocket-propelled grenade launcher. The mad knight continues his charge. At a range of 14 feet the policeman pulls the trigger. He does not miss his target.

"I call it my Sir Lancelot routine," says Mark Draper, recalling the incident a year on. "The cop was pointing the gun at me, shouting `Stop!' But I kept running. I saw the muzzle flash; I heard the report; I felt the impact on my chest. That same instant I knew was dead."

Mr Draper knew wrong. He recovered consciousness - he cannot remember how long afterwards - in a police cell. No wounds, no blood. Just a bruise and a bad headache.

The policeman had shot him, not with live ammunition, but with a "beanbag" filled with lead pellets, one of the latest of a number of new, non-lethal weapons developed for use by police forces around America by scientists at the Department of Justice in Washington. Certainly, no one could have blamed the police for shooting him, said the 39-year-old Mr Draper.

"The cops were well within their rights to kill me. If it hadn't been for the beanbag I wouldn't be here talking to you.In the circumstances, what the police did was the proper response and a very compassionate one."

The circumstances were that Mr Draper, who at the time was vice-president of a construction engineering business in Fremont, California, was in what he describes as a "dangerously twisted" state. An alcoholic for 15 years, he had just been discharged against his will, heavily doped up with medication, from a rehabilitation centre. He went home, drank two whiskies, "went crazy", and decided he wanted to die.

"But I'm a Catholic and my faith forbids suicide, so I rang up the cops and told them, `Look, I want you to send over some guys and I'll come out with a sword and then I want your guys to kill me.' " The police promptly turned up at his door, but first they tried to negotiate with him. He would not listen.

"Medieval armour is my hobby. I had all this stuff up on the shelves. So I figured: `I'm gonna go out and get shot. Hell, I might as well throw it on.' "

Save for the fancy dress, incidents like this one, which occurred in May last year, are not all that uncommon in America. Typically in the past the police response, if persuasion failed, was to beat the suspect into submission or shoot him. The beanbag device, which is indeed fired from a modified grenade launcher, has already saved the lives of numerous criminals and would-be suicides. Only last week police in Michigan succeeded in stopping a man from shooting himself through the head by knocking him down with a beanbag projectile.

Researchers sponsored by the science and technology branch of the Department of Justice, the National Institute of Justice (NIJ), are working on a variety of what they call "less-than-lethal weapons" to combat crime. The premise behind the initiative is that law enforcement has not kept up with the times. Most police forces, says David Boyd, head of the NIJ project, "are still equipped much as Wyatt Earp was in the late 19th century and still have the same basic options when confronting a subject".

A paper published last year by the NIJ noted that the British police in Wyatt Earp's time developed some of their more sophisticated investigative techniques after reading Conan Doyle's Sherlock Holmes. Life today continues to imitate art. Some of the technology Mr Boyd's team is hoping to make available to police officers in the field conjures images of Spiderman, Star Trek and James Bond's "Q".

Assisted by US military intelligence researchers, the NIJ is developing weapons that fire "ensnarement nets"; thermal guns that dramatically increase a target's body temperature; chemical darts; guns that fire electro-magnetic beams; blinding strobe lights; liquid stun guns; "sticky foams" and "aqueous foams" that can immobilise more than one person at a time.

There are also plans to develop a back-seat air bag for police patrol cars, useful to restrain troublesome prisoners; tyre-deflator systems for use at border checkpoints; and pepper-spray launchers.

Most of these devices will not have been fully tested for practical application until the end of the century, NIJ researchers say. But they are adopting a policy of the sooner the better, because the government has found that both the police and the general public are eager for crime-fighting solutions that do not always require that fire be met with fire.

"Citizens demand that the police employ no more force than warranted, not only to avoid undue permanent injury, but also to preserve their right to due process," Mr Boyd says. "If a technology was available that could subdue an unco-operative suspect without injury, the Los Angeles riots in 1992 might have been avoided, as well as the subsequent loss of 42 lives."

The technology available in May last year not only saved Mr Draper's life, it gave him a new lease on it. He did have to spend two weeks in an insane asylum, and he was given a two-year suspended jail sentence by an indulgent court. But he has been sober ever since and, within six months of his "Sir Lancelot" escapade, he got his job back.

"Everyone, starting with the police, has treated me with great kindness," he said. "I wouldn't be here talking to you today if it hadn't been for that beanbag. But I'll tell you something: the friggin' thing works. It's got a kick like a horse."

A sci-fi arsenal

Sticky Foam: A gun will be developed capable of firing multiple rounds of a sticky, viscous material that immobilises the limbs. Useful to control prison riots.

Aqueous Foam: Converts a room, where (for example) hostages are being held, into a bubble bath. Prevents aural and visual communication between suspects.

Ensnarement Net: Launched like a teargas canister, it will have a range of 100ft, allowing police to trap a fleeing suspect without giving chase or opening fire.

Thermal Gun: Can be fired through a wall, instantly raising a target's body temperature to an immobilising 107F.

Chemical Darts: Like the projectiles used to incapacitate wild animals. The challenge is to find a chemical agent that will knock out, but never kill.

Disorienting Pulsed Light: A flash-bang device that induces temporary blindness. Police officers would wear special goggles, time-synchronised with the flashes.

Liquid Stun Gun: A battery-charged launcher that releases an electrically charged spray.