There has also been a call to overturn historic cannabis charges, if the private members bill from Labor backbencher Michael Pettersson passes.

The ACT Legislative Assembly's health committee, which has been scrutinising the legislation for almost four months, overwhelmingly recommended the bill be supported, but with modifications.

The committee's recommendations include;

But the bill still poses problems through its interaction with Commonwealth law.

The bill would remove cannabis possession under 50g as an offence for adults under the ACT's criminal code, thus legalising it.

However cannabis is still a controlled drug under Commonwealth law.

Under the Constitution, where state law is inconsistent with federal law, Commonwealth law wins out.

ACT Policing told the committee cannabis users could see even bigger fines and more jail time if police were put in a position where they had to enforce the harsher Commonwealth laws, because of the absence of more lenient territory legislation.

Even Chief Minister Andrew Barr, who has signalled his support for the bill, acknowledged it would still be risky possessing and growing cannabis even if the drug is legalised in the ACT, because that conflict was "untested".

But the committee was of the view a slight tweak to the legislation to include an express authorisation for the use or cultivation of cannabis by individuals for personal purposes could solve the tension.

Failing that, should Canberrans be prosecuted under the Commonwealth criminal code, the committee said the ACT government should "intervene in any prosecution by the Commonwealth of ACT residents who cultivate or possess cannabis ... to defend the intent of the bill".

It is unclear what form that intervention would take.

ACT Attorney-General Gordon Ramsay said he had the power to instruct the solicitor-general to conduct a high-level intervention, but that would be more about arguing the principles of law than stopping a prosecution.

While such an intervention was "several steps down the track" and the government would need time to formally respond to the recommendations, Mr Ramsay signalled the government would still likely support the legislation.

"We think it's fundamentally important that the Canberran assembly should be able to make legislation according to the values of the people of Canberra - that's a fundamental territory right," Mr Ramsay said.

"We know that people, as the Canberra Liberals have already started to do, find all sorts of reasons why things shouldn't go ahead. We're looking to see how it is that we can uphold the values of the Canberran population and will be responding accordingly."

Liberal politician Vicki Dunne dissented from the committee's recommendations, saying neither the bill or the amendments were fit for purpose.

Mrs Dunne said the fact people used cannabis today despite it being against the law was not a reason for legalising it, as that logic did not follow for other crimes like murder.

However Labor backbencher Bec Cody said the war on drugs had been a "disaster" and the ACT needed to do what it could to solve the problems caused by prohibition.

She said Mr Pettersson had "pointed out to all of us that we can and should do more to end the ridiculous policy of prohibition".

Speaking to The Canberra Times, Mr Pettersson said including an express authorisation in the legislation was "smart and not particularly harmful".

Now the inquiry was over, his bill could come back before the parliament at any time.

"I know the ACT community is supportive of the ACT legalising small amounts of cannabis and I'm committed to pursuing this," Mr Pettersson said.

The committee report came the same day the government moved to create a new Drug and Alcohol Court.

It will introduce legislation to allow courts to issue substance dependent offenders with a Drug and Alcohol Treatment Order.

The court will begin accepting its first offenders later in the year.