Left map shows the % of the vote received by resigning unionist anti-agreement candidates. Right map shows the % of the vote received by pro-agreement candidates. Bottom map shows the winning party by constituency - in all constituencies but Armagh and Newry, resigning unionist candidates were re-elected.
The SDLP and Sinn Féin regarded the resignations as a publicity stunt, and were reluctant to take part in the resulting by-elections. In the event, they contested only the seats which they believed to have an anti-unionist majority.
The Alliance Party of Northern Ireland instructed its branches to nominate a candidate for each by-election, but many were reluctant, and ultimately, the party stood in only five seats. The small Workers' Party stood in nine seats.
It appeared that the incumbent would be the only candidate in four constituencies. This would have produced the first uncontested elections for the House of Commons since the Armagh by-election of 1954. In order to ensure that there was a contest and that the Unionists would be able to demonstrate their point, Wesley Robert Williamson changed his name by deed poll to "Peter Barry", Peter Barry being Minister for Foreign Affairs of the Republic of Ireland. "Peter Barry" stood in these four constituencies under the label "For the Anglo-Irish Agreement", allowing a contest, but did not campaign.
The unusual circumstances led this to be the greatest number of UK parliamentary by-elections held on a single day.
Results
Aggregate results
The aggregated results for all constituencies are shown below. Changes are compared to those for the 15 constituencies in the 1983 general election.
Vote share by party position on Anglo-Irish Agreement
Anti-Agreement Unionists
71.6%
Pro-Agreement candidates
21.8%
Anti-Agreement Republicans (Sinn Féin)
6.6%
All but one of the Unionists were re-elected, many with extremely large majorities. The largest of all went to Ian Paisley in North Antrim. He won 97.4% of the vote, the highest percentage polled by any candidate in a UK by-election since the 1940 Middleton and Prestwich by-election.
The sole exception to this pattern was the Newry and Armagh by-election, where Seamus Mallon of the SDLP was able to take the seat. Former Cabinet Minister Enoch Powell was able to narrowly survive a strong challenge from the SDLP in South Down and was subsequently defeated at the following year's general election. In the western constituencies of Mid Ulster and Fermanagh and South Tyrone, the Unionist candidates were able to survive with less than 50% of the vote due to a split Nationalist vote. Both seats were gained by Sinn Féin in later elections.
The results of the fifteen by-elections were cited by Unionists as a rejection of the Agreement by the Northern Irish electorate, but did not succeed in repealing it.
