Kingston's poorest neighbourhoods, Junior Spence tells a tale he describes as incredible: one day he was arrested by police -- for smoking marijuana! "I could not believe it,'' said the 23-year-old, who months later remains befuddled over the arrest that landed him in jail for a few days and cost him a $20 fine.

"Everybody smokes ganja. The police never hassle them!'' Spence found out the hard way that's not always true. Even though "ganja'' is revered by Jamaica's famed Rastafarians and smoked regularly by many ordinary Jamaicans, it remains illegal.

One critic, Sen. Trevor Munroe, is sponsoring a motion in parliament to study marijuana's medical value, examine how widely it is used and allow possession of small amounts.

That would offend Washington, which considers Jamaican marijuana an American problem because much of it ends up in the United States.

The proposal's chances appear slim because the government opposes it. But it has spawned debate.

"The politicians are afraid of making America angry, so they do as they are told,'' said John Elvove, 46, a construction worker who, like most people interviewed, opposed the laws against marijuana.

Despite the stereotype of reggae-listening pot smokers in dreadlocks, many Jamaicans insist theirs is a conservative society.

The number of users is in dispute, but the smell of ganja is everywhere in Kingston. Sociologist Richard Crawford of the University of the West Indies says at least 45 percent of Jamaicans "have smoked, do smoke and will smoke marijuana.'' Still, many others view it as a negative influence in a country that suffers from a moribund economy and growing violent crime.

Winston Mendes-Davidson, head of the Medical Association of Jamaica, called it "the single greatest detriment to the development of Jamaica.'' Some 6,000 people -- out of a population of 2.6 million -- were detained last year on marijuana-related charges, including possession, selling and trafficking. Officials admit they fear a more serious crackdown will spark violent confrontations.

"During something like a football game ... we are not going to be searching for persons with ganja because that would involve an assault on the stadium,'' said A.J. Forbes, a police spokesman.

Indian indentured servants brought marijuana to Jamaica in the 19th century.

Its use as a medicinal herb spread rapidly among plantation workers. Ganja tea was brewed to alleviate aches, and rum-soaked marijuana was rubbed on the body to cure coughs, colds and fevers.

"The harsh aspects of life -- the back-breaking work in the field for low wages and poor living conditions -- made it very attractive as a way to relax and escape,'' Crawford said.

Use spread with the advent of Rastafarianism in the 1930s, whose adherents, mostly the poor, considered marijuana a holy herb.

But it was not until the 1960s and 1970s, when Bob Marley and other reggae icons popularised the culture of the poor among better-off Jamaicans, that marijuana's popularity began to filter through the island's rigid class structure and gain a wider acceptance.

Today, Jamaica is the largest producer of marijuana in the Caribbean. Between 1992-98, the United States provided $7.8 million to Jamaica's effort to eliminate production and trafficking. The most popular means employed has been sending squads to the fields to manually chop down the plants.

Crawford said young Jamaicans -- people under 30 are the majority -- use ganja far more than those who grew up in the early years of independence or under the British, who ruled until 1962.

"Our parents were all terribly scared of this thing, and told us to keep away from ganja,'' he said. Now, "the values have changed.'' Green, green, grass of home: Royal Gazette photographer Ras Mykkal investigates a marijuana field while on a trip to Jamaica.