No one likes a political party or a politician who flip-flops at the sight of a poor popularity poll or to suit some perceived interest group.

When the issue of medicinal cannabis and a trial in Tasmania was first mooted it received a disappointingly swift slap-down from the state government.

It is hard to know whether the issue was too controversial or whether some in the Liberal Party had philosophical objections that clouded their thinking.

It is one thing to be conservative and quite another to be so conservative in your thinking that opportunities are missed.

Regardless, in budget estimates on Monday we saw a refreshing change of heart from Health Minister Michael Ferguson who has now supported a trial and assessment of the product.

Mr Ferguson, however, has quite rightly stated that the government's support is based on a proper evidence-based study, strong regulatory framework and appropriate approvals from national regulators.

"If cannabis is to be approved as a medicinal substance beyond the indications for which it is currently approved, it must satisfy the same rigorous process that any other therapeutic agent would undergo," he said.

Australians would expect no less.

Despite many testimonials about the benefits of cannabis oil for severely ill people, the product must be totally safe before it is publicly released.

Both the Labor and the Greens described the decision as a backflip, although it was interesting to note there was no encouragement for a trial under their watch.

Either way the trial now appears to have tripartisan support and if the product can relieve pain for some people then it will be a valuable addition to our medicinal armoury.