Counseling, rather than school suspension, was found to be a more effective means of combating marijuana use in schools, a new study found.

The study, conducted by researchers at the University of Washington and in Australia, compared drug policies at schools in Washington state and Victoria, Australia, to determine how they impacted student marijuana use. The results were published online in the American Journal of Public Health.

The results surprised researchers, according to a news release. Students attending schools with suspension policies for illicit drug use were 1.6 times more likely than their peers at schools without such policies to use marijuana in the next year, and that was the case with the student body as a whole, not just those who were suspended, researchers found.

“That was surprising to us,” said co-author Richard Catalano, professor of social work at the University of Washington’s School of Social Work, in their news release. “It means that suspensions are certainly not having a deterrent effect. It’s just the opposite.”

The study found that students attending schools with policies of referring pot-using students to a teacher to discuss the dangers of marijuana use were 50 percent less likely to use marijuana later on. Other ways of responding to policy violators such as sending them to educational programs, referring them to a school counselor or nurse, expelling them or calling the police were found to have no significant impact on marijuana use.

Data for the research come from the International Youth Development Study, a long-term initiative started in 2002 to examine behaviors among young people in Washington and Victoria. The two states were chosen since they are similar in size and demographics, but differ considerably in their approaches to drug use among students. Washington schools are more likely to suspend students, call police or require offenders to attend education or cessation programs, the researchers noted, while Victoria schools emphasize a harm-reduction approach that favors counseling.

Researchers surveyed more than 3,200 seventh- and ninth-graders and nearly 200 school administrators in both 2002 and 2003. Students were asked about their use of marijuana, alcohol and cigarettes and also about their schools’ drug policies and enforcement. In both survey years, marijuana use was higher among Washington students than those in Victoria — almost 12 percent of Washington ninth-graders had used marijuana in the past month, compared with just over 9 percent of Victoria ninth-graders.

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