Paucity of dagga research rebounds on expert

A British psychiatrist and neuropsychopharmacologist specialising in the harmful effect of drugs on the brain was cross-examined on his testimony in the third week of the dagga trial in the High Court in Pretoria yesterday.

Advocate Reg Willis, representing one of the defendants, Doctors For Life International, asked expert witness Professor David Nutt how, if there was insufficient research on cannabis because it was an illegal substance, could the available data on its harmful effects be accurate?

Jules Stobbs and Myrtle Clarke, dubbed the “dagga couple”, are asking the court to legalise the use of cannabis by adults after they were arrested in 2010 for possession and dealing in it. The national director of public prosecutions, six government ministers and Doctors For Life International are opposing this.

Willis questioned the veracity of Nutt’s statement that cannabis was not as harmful as alcohol and tobacco, following his testimony last week that research on illegal drugs was limited.

“You said it is difficult to do research as the drug is illegal and that research had data problems. What is the missing data, then? Why did you present data as evidence when you said there is no real data as the substances were illegal?”

Nutt said his evidence was based on the best estimates from the little research scientists and professionals had been able to conduct.

“Yes, we have data problems. Therefore, we have to use the best estimates. We do not know exactly how many people use illegal substances, but we know how many use alcohol.

“Data on illegal drugs is always less good than that on legal drugs. One has to make decisions on the best data they have and use the best people to analyse that data,” he explained.