DEBATE IS RE-IGNITED: IS POT A 'GATEWAY'?

The major study on medical marijuana released last week did more than
conclude that marijuana may help treat certain sick and dying patients.
Eminent researchers also tackled the long-debated question of whether
marijuana leads users to abuse hard drugs such as cocaine and heroin.

Their finding: "There is no conclusive evidence that the drug effects of
marijuana are causally linked to the subsequent abuse of other illicit drugs."

This statement elicited sweet satisfaction from marijuana proponents, but
it infuriated many drug abuse experts and prosecutors and some lawmakers.

"In my mind, there is no question about the statistical relationship"
between marijuana and the abuse of hard drugs, says Joseph Califano, a
former U.S. secretary of Health, Education and Welfare. Califano cites
studies showing that a child who uses marijuana before age 12 is 79 times
more likely to use harder drugs than a child who never smokes marijuana.

Califano says the connection is more statistically significant than the
1964 surgeon general's report that first linked smoking and lung cancer.
"To say there is no relationship - that is preposterous."

Califano is currently head of the National Center on Addiction and
Substance Abuse (CASA) at Columbia University in New York, perhaps the
nation's foremost promoter of the "gateway theory" - that marijuana is a
gateway drug that leads to heroin and cocaine.

The medical director of CASA, Herbert Kleber, says research on the brain's
pleasure center may provide more evidence of a direct link. "We don't have
the smoking gun yet, but we are closing in," he says.

Portland, Ore., medical professor John Benson, co-director of the Institute
of Medicine study, defends it, but also stresses, "We are, of course,
worried about the association between marijuana and further drug use,
particularly among teen-agers."

He also noted that the study, commissioned and paid for by the White House
Office of National Drug Control Policy, "came out strongly against smoking"
marijuana.

In the report, Benson and University of Michigan researcher Stanley Watson
say that because marijuana use usually precedes hard drugs , "it is indeed
a 'gateway' drug" in some sense.

But, they continued, "because underage smoking and alcohol use typically
precede marijuana use, marijuana is not the most common and rarely the
first 'gateway' to illicit drug use."

The factors that best predict use of illicit drugs beyond marijuana are
actually "age of first alcohol or nicotine use, heavy marijuana use and
psychiatric disorders," the study said.

The most frequent explanation for marijuana as a gateway drug is that
youths who use it enter the world of illegal drugs, where they have a
greater opportunity and are under greater social pressure to try other
illegal drugs.

This interpretation "is supported by - although not proven by - the
available data," the report conceded.

But, the report also argued, the data is unconvincing. Too often, the data
provides no indication of what proportion of marijuana users become serious
drug abusers, only that drug abusers usually use marijuana before they
smoke crack cocaine or inject heroin.

Chuck Thomas of the Marijuana Policy Project says that if there is anything
about marijuana that drives teen-agers to hard drugs, it is the likelihood
they'll have to buy it from drug dealers. His group, based in Washington,
D.C., seeks to eliminate jail penalties for marijuana use.

Lynn Zimmer, a sociologist at Queens College in New York and co-author of
the book Marijuana Myths, Marijuana Facts, says the gateway theory is as
likely to be true as the idea that early bicycle riding "causes" motorcycling.

Marijuana use "may give you a hint that your kid might be interested in
other drugs," she said.

Zimmer favors an approach used in the Netherlands that separates the
marijuana market from other drugs by allowing small amounts of marijuana to
be sold to people over 18 at certain businesses.

Zimmer's attitude is not shared by most law enforcement officials. "People
who work in our drug court tell me" that marijuana and more serious drugs
are connected, says Doug Moreau, the district attorney in Baton Rouge.

"It's only common sense. There's a natural human tendency" once you are a
regular user of one drug "to start looking for something that gives you a
bigger kick."

Santa Fe District Attorney Henry Valdez says that "almost every case we've
had" of major drug use began with marijuana, and he thinks social pressure
as much as anything leads people to use hard drugs after they're tried
marijuana.

The Institute of Medicine report drew criticism from Rep. John Mica,
R-Fla., chairman of the House Government Reform Subcommittee on Criminal
Justice, Drug Policy and Human Resources.

Mica announced plans to hold hearings in late April on drug legalization
and medical marijuana, and called the Institute of Medicine report "the
biggest waste of money in the entire war on drugs."