British spy agency MI5 investigated Irish construction workers in England during the 1970s through a bogus consulting company and had them blacklisted with major employers as a result, the Irish Times has revealed.

The British Information Commissioner David Clancy told the House of Commons that a front organization called the Consulting Association was likely an MI5 front with the specific task of blacklisting Irish workers in Britain.

Members paid $5,000 for information from the Consulting Association which researched the background of workers for them.

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Some of the major British construction companies were  involved in the subsequent blacklisting, including Laing and McAlpine, who had many Irish workers seeking employment.

Clancy told the committee that the information on Irish workers was “highly personal” and included information about their wives, education, political leanings and even the cars they owned.

Unions were also involved in helping to screen Irish workers. There is evidence that one union sent names of Irish members to the Consulting Association “to screen out extremist elements operating without official union sanction.”

In July, nearly 90 workers launched a legal action against one firm listed, Robert McAlpine, alleging it had been involved in an unlawful conspiracy.

Irish workers demonstrate over names been included on