VIOLENT USERS ANTI-SOCIAL BEFORE CANNABIS - STUDY

Wellington - A Dunedin study has traced the high level of violence among
cannabis-dependent people to their history of anti-social behaviour and the
illegal drug economy, rather than using the drug itself.

A report released in London last week showed cannabis-dependent
21-year-olds were nearly four times as likely to be violent as their peers.

The report also found those who were alcohol dependent were nearly twice as
likely to be violent than other 21-year-olds and those suffering from
schizophrenia were 2 1/2 times more likely to be violent.

The study of 961 people born in Dunedin was carried out by the Dunedin
Multidisciplinary Health and Development Research Unit, whose director
Richie Poulton said yesterday there was no relationship between occasional
users of cannabis and violence.

The problem was with the "small subset" who used large amounts of cannabis
and were deemed to be dependent on the drug.

Dr Poulton said the Dunedin group were studied as 21-year-olds for
violence, because that age was the peak for violent offending and mental
health problems.

The study found that the people diagnosed as dependent on cannabis "had a
long history of anti-social behaviour, going right back to when they were
three years old.

"They were being naughty, beating up other kids in the sandpit, being
disruptive, then they went to stealing milk money, then they went to
beating up bigger kids in the schoolground, then they converted a car . . .
it goes on and on and on."

The study found that most of the cannabis-dependent people were also drug
dealers and involved in the black economy.

"When stuff doesn't work out right they just resort to violence," Dr
Poulton said.

But the psychiatrists said violence among alcohol-dependent individuals was
best explained by "substance use" in the two hours before offending.