Queensland MP Steve Dickerson has defected from the Liberal National Party to join Pauline Hanson's One Nation ahead of the next state election.
Dickson told reporters his main reason for quitting the party was the urgent need for better access to cannabis oil for terminally ill patients.
He said he had been affected by the families of terminally ill patients who had reached out to him for help after authorities shut down a cannabis oil supplier in South Australia.
Dickson said he had reached out to Prime Minister Malcolm Turnbull and reached out to Prime Minister Malcolm Turnbull and Queensland Premier Annastacia Palaszczuk to grant them amnesty.
"A young lady who was in my office, just this Monday gone, has a brain tumour and was using this exact same product so that she can stay alive," he said.
"We have two choices to make. We can follow bureaucracy, which is a written piece of paper, or we can save a life. My choice is to save a life.
"We cannot, under any circumstances, allow a child to die - and that's the situation that we're all caught up in today."
Hanson had flagged the announcement on Thursday but on Friday she said she did not approach Dickson about his defection.
"No deal was ever done and I never at any stage encouraged Steve to come across," she said.
"I can't do it alone. I need strong-minded people, as well, who are there for the right reasons. That's why I'm so proud of Steve. Medicinal cannabis is an issue for him, but he has spoken to me about so many other issues as well, that we need to see Queensland move forward."
Dickson's move gives One Nation a valuable vote in Queensland's hung parliament.
Dickson's move is the latess of expansions for Hanson's One Nation, which is running 40 candidates in the upcoming WA state election.
The next Queensland state election isn't due until 2018.
"Now you have me as leader of this party and now you have Steve on board, with his experience, and they won't know what the hell happened to them by the time we have finished," she said.
Queensland Greens Convenor Andrew Bartlett says the defection is a huge blow to the LNP's credibility in the state, and shows the difference between One Nation and the LNP is smaller than ever.
"As we have already seen from a number of One Nation candidates, the party has no plan or policy to strengthen the economy and tackle rife unemployment," he said.
"Instead they single out and attack vulnerable groups in the community, whether it is welfare recipients, gays and lesbians, Muslims or migrants – an approach which more and more LNP members are doing with growing frequency."
In Queensland, meanwhile, One Nation candidate for Mulgrave Peter Rogers has offered to resign days after his blog said the death of Syrian toddler Aylan Kurdi was fake despite devastating photographs of the drowned boy.
PRESS RELEASE: After talks with party executive Pauline Hanson's One Nation candidate for Mulgrave, Peter Rogers, has offered to step down. pic.twitter.com/bJSY9ff8UY— Pauline Hanson (@PaulineHansonOz) January 13, 2017
He's potentially the second Queensland candidate to leave the party after Shan Ju Lin was disendorsed last week after making homophobic comments on Facebook.
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