Western Australia will abolish its six upper house districts in a major overhaul following "undemocratic" outcomes at the state election.
Legislative Council MPs will instead be elected by the entire state, with regional votes to no longer carry greater weight than city votes.
The move is heavily opposed by the WA Nationals, who claim it will disenfranchise regional voters by reducing their representation.
WA will also scrap group voting tickets, which have been manipulated through so-called "preference harvesting" to get minor parties elected.
The Labor government will introduce legislation this week to enshrine the changes, which were endorsed by an expert committee led by former governor Malcolm McCusker.
Premier Mark McGowan had insisted before the March election that electoral reform was "not on our agenda" but soon after tasked Mr McCusker with examining the system, in particular malapportionment in regional areas.
Each upper house region currently elects six representatives regardless of their populations.
Attorney-General John Quigley said votes cast by people in the Mining and Pastoral region at the last election were worth 6.22 times more than those cast in the metropolitan area.
Ending malapportionment could reshape the upper house given the Nationals' traditional dominance in regional areas.
Labor already holds 53 out of 59 lower house seats and an unprecedented upper house majority after a landslide election victory.
Mr Quigley on Wednesday insisted the reform would make WA's electoral system fairer.
"I do not accept that proposition at all that these laws are designed to favour Labor," he told reporters.
"The party that gets the larger percentage of the vote will get the larger percentage of the seats. That's what should happen in a democracy."
He insisted it would not come at the expense of regional representation.
"My message to regional voters is at this stage, Labor is the party of the regions," he said.
"We have 21 members across the regions in Western Australia, more than any other party. We intend to be the party of the regions and that members will be living and working in the regions."
Under the changes, voters will elect 37 upper house MPs rather than the current 36.
WA will abolish group voting tickets, which allow parties to dictate the preference distribution when electors vote above the line.
It comes after Daylight Saving Party candidate Wilson Tucker was elected in the Mining and Pastoral region despite polling just 98 votes - a figure believed to be the lowest primary vote for a candidate elected to any parliament in Australia.
His victory was made possible by complex preference deals which also catapulted Legalise Cannabis WA candidates to victories in the South West and East Metro regions.
The Greens were reduced from four upper house MPs to one despite comfortably outpolling the pro-cannabis party.
"There's gaming and rorting of the system going on in Western Australia that needs to be fixed ... the whole system is broken," Mr McGowan said.
"It needs to be repaired and that's what these measures do."
