On 27 November 1944, a special conference of the National Party voted to co-operate in the formation of the new Liberal Party of Australia and nominated its parliamentary leader Ross McDonald and state president Jim Paton as delegates to the Albury conference.

The coalition strengthened its majority by gaining the support of Independent MPs Harry Shearn and William Read.

It renamed itself the Country and Democratic League (CDL) and retained a significant amount of support at the 1947 election, winning 16.2% of the vote and 12 seats (up 2 from 1943).

[16] In the December 1949 federal election, the LCL and CDL agreed to campaign together as a united front against Labor, with a joint Senate team and a full exchange of preferences in three seats where each party had candidates.

[17][18] The federal Liberal/Country coalition led by Robert Menzies won the election, winning 5 out of the 8 lower house seats in Western Australia.

The Hawke government was elected to second term in 1956, winning a larger majority and reducing the coalition to 19 seats (11 LCL and 8 CP).

In 1974, the party won a landslide victory in the state election, under the leadership of Sir Charles Court.

The government's decision to allow mining and development in sensitive environmental areas attracted criticism from the Opposition.

[citation needed] In the late 1970s, the Liberal Party faced increasing pressure from the emerging environmental movement, which was concerned about the impact of industrialisation and development on the state's unique natural heritage.

[citation needed] The party's response was mixed, with some members advocating for greater environmental protections, while others argued that economic development should take priority.

[20] However, Harvey resigned a year later and was replaced by first-term MP Zak Kirkup in November 2020.

[21] The two lower house seats were retained by David Honey and deputy party leader Libby Mettam.

[4] Under the Public Sector Management Act, the Liberal Party would not have qualified for important Parliamentary resources as a result of losing opposition status.

[25] After election, Mettam said she would curtail the influence of "The Clan", a group of factional powerbrokers within the party.