Scott Morrison is set to face a headache when parliament resumes next week after a Northern Territory senator defected from the Coalition to join the crossbench.
Senator Sam McMahon has resigned from the Country Liberal Party and is expected to continue to serve as an independent for the foreseeable future, meaning the Coalition is down one seat in the upper house.
Senator McMahon’s resignation comes as two other Coalition senators, Alex Antic and Gerard Rennick, flagged withholding their votes for government bills until laws were brought in to override state vaccination mandates, paving the way for a difficult first sitting week for the government.
Senator McMahon’s move leaves the government without any parliamentary representation in the NT.
Senator McMahon said she had wrestled with the decision but felt she “no longer (has) the confidence of or in the CLP”.
She said in a statement on Monday that she would announce her intentions regarding the next election “as the date draws closer”.
Her resignation comes after she lost a fierce preselection battle last year to be the party’s top senate candidate at the next federal election to former Alice Springs deputy mayor Jacinta Price.
Senator McMahon had the support of Nationals leader and Deputy Prime Minister Barnaby Joyce in the lead-up to the battle.
“There are a number of unresolved issues beyond the preselection,” Senator McMahon said on Monday.
“These issues include formal complaints lodged with management committee that have not garnered a response let alone an acknowledgment.”
Senator McMahon won preselection to replace Nigel Scullion as the CLP’s lead senate candidate at the 2019 federal election, at which she won.
She chose to sit with the National Party in federal parliament.
Senator McMahon had last year been accused of being drunk in parliament, an allegation she refuted.
Reports emerged in June last year that at least 10 unnamed senators from across the chamber had reason to believe the senator was heavily inebriated.
Senator McMahon’s spokesperson at the time said she had just been feeling “unwell” and the allegations had been an attempt to undermine her ahead of the preselection.
“This is part of a political machine manufacturing any reason to dislodge Senator McMahon before preselection, even fictional ones,” spokesperson Ashley Manicaros said at the time.
Senator McMahon’s defection to the senate is set to cause a headache for the Morrison government when parliament resumes next week.
In December, Senator McMahon allegedly tried to punch Nationals federal director Jonathan Hawkes after a Christmas party.