During a period of over 40 years, Smyth sexually abused and indecently assaulted at least 143[1][2] children in parishes in Belfast, Dublin and the United States.

The Norbertines, also known as the "Premonstratensians," were aware of Smyth's crimes as early as the late 1970s, yet they did not report him to either the Garda Síochána or the Royal Ulster Constabulary.

Norbertine Father Bruno Mulvihill made several attempts to alert church authorities about the abuse committed by Smyth.

[4] Reviewers of the case differ as to whether there was a deliberate plot to conceal Smyth's behaviour, incompetence by his superiors at Kilnacrott Abbey, or some combination of factors.

Cahal Daly, both as Bishop of Down and Connor, a diocese where some of the abuse took place, and later as Cardinal Archbishop of Armagh, is recorded as having been privately furious at the Norbertine "incompetence".