1955 Alberta general election

The 1955 election was brought on after Liberal leader James Harper Prowse questioned the confidence of the government in question period regarding members of the Social Credit caucus who had had dealings with the Alberta Treasury Branch. Manning was angered by the question and had the Lieutenant Governor dissolve the assembly despite having two more years left in his term.

On the last day of the campaign Ernest Manning barred candidates Roy Lee and John Landeryou from running as official Social Credit candidates. However, due to the ballots having already been printed, the two men were still listed under the Social Credit name. Lee and Landeryou had violated the Legislative Assembly Act by renting a building to the provincial government.[4]

Following this election, the Social Credit government did away with the Alternative Vote Instant-runoff voting system, that had been in place in the rural constituencies, and the PR through Single Transferable Vote system in Edmonton and Calgary, both of which had been in place since 1924.

Under Single Transferable Voting, results would take up to five days to count the necessary vote transfers, before the last member was declared elected. This was especially problematic, in Edmonton that elected seven members. The resulting representation was very well balanced, with as many as four parties commonly elected in each major city.

As well, the government in 1955 had lost four local elections in rural constituencies due to vote transfers held under IRV, when its candidate had received the largest portion of the vote in the first round but was not elected to the seat after re-distribution of the ballots in later counts. The cancellation of the IRV system was meant to prevent this in the future. In four constituencies the SC candidate had received plurality of first-choice votes but was not elected when another candidate surpassed his lead through vote transfers conducted under IRV. This indicated to the government that the supporters of the opposition parties were beginning to support each other in a joint effort to defeat the government. (One historian has stated that there were 20 constituencies like this in which the SC at the end won only five but that number is too high. There were 16 constituencies in which, in the first count, no candidate took the majority of the votes. Only in these constituencies was it necessary to hold more counts (involving re-distribution of some votes in accordance with voters' marked back-up preferences). Even where vote transfers were conducted and more counts held, mostly the candidate leading in the first round won the seat in the end, but there were four constituencies (Acadia-Coronation, Athabasca, Lac Ste. Anne and Vermilion) in which the leading candidate in the first round was not the candidate with the most votes at the end and thus did not win the seat. The victim in all four cases was a SC candidate.)

The government presented the complicated voting procedure as reason to shift to First past the post, a voting system that was simpler but also was expected to give the government more seats. The 1955 election saw the election of the largest opposition caucus that Manning faced during his 25 years as premier (although it was just 40 percent of the seats in the Legislature). As well, it was the most opposition members Social Credit would face during its 36 years in power.

After the shift to First past the post the next election (1959) saw the government win all but four of the seats in the Legislature, far more than its due share of the vote.

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