Revenue officials warned of potential tax law changes arising from the family referendum before Ministers claimed the proposal had no tax implications, according to newly-released files that raise fresh questions about the truthfulness of the Government.

Commenting on the revelations, Michael McNamara, TD, said the government, “on the recent referendum, on immigration and how they have labelled the response of communities, and throughout this Dáil term, have been the greatest purveyors of misinformation in this State”.

Campaigners for No warned before the vote of “long-term consequences” for tax law. But when the Government was asked, it stated in unambiguous terms that there would be no tax impact.

“In relation to your specific question, the proposed amendment will not affect taxation, succession or family law,” the Government said during the campaign.

Now Revenue files – released by the Department of Finance under the Freedom of Information Act – show how the tax authority noted a lack of clarity “on the extent and scope” of how the proposed Constitutional change would “interact” with tax law.