Dope-smoking Canberrans should be able to join clubs where gardeners can cultivate their cannabis crops for them, a Legislative Assembly inquiry has been told.
Labor backbencher Michael Pettersson's private member's bill would legalise cannabis possession under 50 grams and allow users to grow up to four plants.
The government has foreshadowed amendments to the legislation that would allow only two plants to be grown up to a household limit of four plants, and introduce wet and dry limits for the drug.
Mr Pettersson told an Assembly inquiry into his bill on Tuesday allowing people to grow their own supply would stop them coming into contact with drug dealers who "have a commercial imperative to push harder and more addictive substances on their clients".
"If we did have to pinpoint a particular point of the process that causes the most harm for the individual that would be the interaction with drug dealers," Mr Pettersson said.
However, he also said that because there was no way to legalise supply under the Commonwealth's drug trafficking framework, people would still need to source seeds or seedlings from the black market.
Greens crossbencher and former cannabis grower Caroline Le Couteur pointed out Mr Pettersson's proposed system of "peasant cultivation" may not work as "history shows us most people aren't interested in growing their own, be it or dope or anything else".
Curtin University's National Drug Research Institute director Professor Simon Lenton agreed, citing research that suggested less than 30 per cent of first-time minor cannabis offenders grew their own cannabis as their main source of the drug.
The 2010 National Drug Strategy Household Survey also reported that only 3 per cent of people who said they had used cannabis in the previous year grew their own supply.
"The Simple Cannabis Offence Notice scheme in Canberra has been in operation for a number of years so there may be a higher of cannabis users growing their own supply in the ACT but I would be surprised if the figure was over 20 per cent of people growing their own cannabis for personal use," Professor Lenton said.
He suggested the supply problem could be fixed by amending the wording of the legislation to allow "cannabis social clubs" to be set up "for the 80 per cent of cannabis users who we estimate won't be prepared to grow their own cannabis".
The clubs, which began in Spain but have since cropped up all over the globe, are not-for-profit organisations that grow cannabis for their members.
Members must be over 18 and abide by a strict set of rules to remain in the club, including that they don't on-sell the cannabis. There are limits for how many members there can be in the club and the maximum number of plants each member can have.
"It’s quite clear occasional users aren't going to have their needs met by a cannabis social club but from what we know the majority of cannabis that’s being consumed in the community is being consumed by people who are more regular users, who are using it on a near daily basis so .... it’s possible that this kind of market would meet the needs for those people," Professor Lenton said.
That model would be unworkable under the current wording of the bill though as it would be a crime to "cultivate" more than five cannabis plants.
Instead, Professor Lenton said it should be made illegal to "own or possess" five or more plants, so a grower employed by a cannabis social club could attend to plants owned by the members without breaking the law.
Mr Pettersson said he was not opposed to cannabis social clubs, but he would prefer a method of distribution that could be regulated and taxed.
However Professor Lenton said there was emerging evidence that systems like that in Colorado actually increased harm in a similar way to alcohol and tobacco marketing.
"That’s obviously not ideal from a public health perspective," he said.
The inquiry continues.