The lawyer for a South Australian woman who admits to supplying cannabis oil to terminally ill people has questioned why charges against her client have only recently been laid.

Hillier resident Jenny Hallam's home was raided by police back in January and products, which she says she only ever supplied to sick people for free, were seized.

Ms Hallam has been summonsed to appear in court in May over allegations she possessed, with the purpose to supply, and manufactured a controlled drug.

Lawyer Heather Stokes said she was "puzzled" about why it took police so long to charge her client.

"You either prosecute her in a timely fashion, which was back in January, or exercise the discretion given the massive public support around the nation and given the political debate, you just let it die," Ms Stokes said.

Jenny Hallam says she never sold her products. ( Facebook: Jenny Hallam )

She said the supply charge carried a maximum of two years' jail while the manufacturing carried a maximum of seven years' prison.

"Don't expect some miracle defence ... this is about whether she should be prosecuted at all, and if so what's going to happen to her," Ms Stokes said.

She said since the raid on Ms Hallam's home there have been a lot of public debate about medicinal cannabis with people sharing "dreadfully poignant" personal stories.

Police could have used discretion, lawyer says

The Federal Government has moved to loosen the importation of medical cannabis and doctors can prescribe it, but it is illegal to possess and manufacture it in South Australia.

Ms Stokes questioned why her client was being prosecuted when the state was likely to change the law, which would have "massive [public] support".

"I'm not going to tell you right now, I refuse to admit or deny on behalf of my client whether she is currently making cannabis oil and supplying people for free."

She said police had a level of discretion when it came to issuing charges.

"You have to wonder why this has occurred, and there are several possible explanations," she said.

"One is it's someone in the police department ... or some recalcitrant politician has asked his minions within to check with SAPOL why they haven't actually filed charges against her," Ms Stokes said.