Ward 4 Blue Mountains City Councillor Brendan Christie has resigned from the Liberal Party.
Cr Christie cited a "toxic environment" in the local party as the reason behind his decision but said he will continue to serve as an independent councillor.
His claims about the local Liberal Party have been strongly rejected by Ward 3 Liberal Cr Roza Sage.
In a statement on Monday, July 3, Cr Christie said: "After careful consideration, I have made the difficult choice to resign from the Liberal Party and continue serving our community as an independent councillor.
"It deeply saddens me to acknowledge that the values of classical liberalism and conservatism, which have guided my actions thus far, are no longer upheld within the party. Equally distressing is the toxic environment that has permeated our local party, where politicking and political games have taken precedence over the true purpose of public service.
"I want to stress that this behaviour is not from all party members, and I appreciate the support of the party members who have supported me through three elections.
"By resigning, I am making it clear that I do not endorse such behaviour which undermines the very essence of public service. I also want to assure my local community that my commitment to them has not wavered. I am immensely grateful for the trust and support you have placed in me over the past 11 years. Your input and feedback will continue to shape my decisions, as it has always done."
Cr Christie was granted a six month leave of absence at the May council meeting this year, with the unanimously-supported motion noting that the council "sends its support to Councillor Christie at this time".
His former Liberal colleague, Cr Roza Sage, said in a statement that the council has "tried to support him through this difficult time".
She added that Cr Christie's "allegations [about the Liberal Party] have not been previously raised and are strongly disagreed with".
A councillor for 11 years, Cr Christie's decision to quit the Liberal Party follows that of former Liberal councillors Daniel Myles and Chris Van der Kley, who both quit the party in 2020. They continued to serve on council as independents, with Cr Myles re-elected at the last council election and Mr Van der Kley narrowly losing his re-election bid.
Blue Mountains mayor Mark Greenhill said Cr Christie was right to call out what he viewed as bad behaviour and offered his "personal friendship and support whenever he should need it".
"I've known and worked on council with him for over a decade and regard him as a good person," he said. "The challenge for us in the current era is to stamp out poor behaviour - including bullying - in institutions whether they be workplaces, political parties or even online."
Cr Christie's resignation leaves the 12-person Blue Mountains City Council with two Liberal Party councillors - Roza Sage in Ward 3 and Kevin Schreiber in Ward 1.
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