There are fears the Government's medicinal cannabis Bill could be missing out on submissions from those who use the product, due to fears the police will use the information to arrest them.
Submissions will close on the Misuse of Drugs (Medicinal Cannabis) Amendment Bill on Wednesday, March 21.
The Medicinal Cannabis Awareness Group's Shane Le Brun told RadioLIVE Drive with Lisa Owen and Ryan Bridge they're having trouble getting their members to put in submissions.
"We've got a big database of patients with some pretty severe conditions," he said.
"[But] we're finding that about 20 percent of them just don't want to put their name on anything to discuss medical cannabis because they're afraid of the police.
"In some cases they've already been hauled over by police a few times for cultivation for personal medical uses."
Users are concerned that if their name and story is on the public record, it would not be difficult for police to find them. Even those who do submit don't want to admit to their own usage.
According to Mr Le Brun, police generally turn a blind eye to medicinal cannabis users - but the second somebody is growing to ensure a stable supply it's a problem.
"There is a high chance of some old-school police officer trawling the records for some cultivators, to get some low hanging fruit," he said.
He wants the police to say they won't do that and that the submitters will be safe going on the record.
However without that guarantee, he's encouraging submitters to follow advice from other groups, including the Drug Foundation.
Mr Le Brun also suggests they make a submission but avoid admitting to cultivation unless it's something that they have already gone to court for.