The looming by-election in Darling Range is the second since Labor's landslide win at the Western Australian state election of 2017, after that which replaced Colin Barnett in Cottesloe in March, and the first in a seat that is competitive with respect to the two major parties. It has been prompted by the resignation of Labor member Barry Urban, in circumstances that would appear to make the by-election a difficult proposition for the government. The seat will be defended for Labor by Colleen Yates, chief executive of Regional Development Australia Perth, against Liberal candidate Alyssa Hayden, who held a Legislative Council seat in East Metropolitan region from 2008 to 2017.
Barry Urban's win in Darling Range was among the more spectacular of Labor's 20 gains at the March 2017 election, having been achieved from a swing of 18.6% the eighth highest of the election, making Darling Range the fourth safest seat lost to the Liberals and Nationals at the election. However, his career unravelled last November when it emerged that a decoration he wore for police service overseas, which he originally claimed to have received for war crimes investigations in Bosnia-Herzegovina, had actually been bought online, and that two British universities he claimed had awarded him degrees had no record for him.
Urban resigned from the ALP shortly after the story broke in November, and announced his resignation from parliament on May 7, a day before the parliament's privileges committee was due to bring down a report on the matter. What remains beyond dispute about his background is that he came to Australia from the United Kingdom in 2000, worked in construction before joining the police force in 2005, and served on Serpentine-Jarrahdale Shire Council.
Darling Range covers the south-eastern reaches of the Perth metropolitan area, taking most of its voters from the South Western Highway towns of Byford, Mundijong and Serpentine. It has existed in name for all but one term since 1950, but it emerged from the one-vote one-value redistribution in 2008 bearing little resemblance to its earlier namesake, most of which had gone to the new seat of Kalamunda. Half of the new Darling Range's voters came from abolished Serpentine-Jarrahdale, and it was duly bequeathed to that seat's Liberal member, Tony Simpson, while Kalamunda went to the member for Darling Range, John Day.
Tony Simpson first had to overcome a notional Labor margin of 0.8% to win Darling Range in 2008, but this was easily achieved with a swing of 6.3%. A further swing of 8.3% followed with the Barnett government's sweeping re-election in 2013, after which he was promoted to cabinet as Local Government Minister. However, he resigned in September 2016 citing a lack of confidence in Barnett, together with Transport and Agriculture Minister Dean Nalder, which triggered an unsuccessful spill motion. His margin in Darling Range was pared back by 2.5% by a redistribution that transferred around 3600 voters in the new urban fringe suburbs of Harrisdale and Piara Waters to Jandakot, balanced by gains of Baldivis east of the Kwinana Freeway from Kwinana in the south, and Sawyers Valley and southern Mundaring from Swan Hills in the north.