In 1987, he mounted a successful legal challenge in the Irish Supreme Court against the Government of Ireland's attempt to ratify the Single European Act without reference to the people in a referendum.
In 1945, Crotty purchased a 204-acre (0.83 km2) farm in Dunbell, not far from Kilkenny, and spent the next two decades putting into practice his developing knowledge of agricultural production.
Crotty was a prolific writer, producing books, pamphlets, articles, and letters on subjects such as economics, history, and Ireland's involvement with Europe.
His final work, When Histories Collide: The Development and Impact of Individualistic Capitalism, was edited by his son Raymond and published posthumously in 2001.
This would allow taxes on inputs and outputs to be removed or reduced and would encourage only those prepared to maximise the potential of their land to remain in farming.
Furthermore, Crotty maintained that Ireland's status as an ex-colony made it unsuited for membership of a bloc of nations that included former colonial powers.
[10] In 1992, he once again allied himself with Anthony Coughlan in urging Irish voters to reject the Maastricht Treaty in the referendum held on 18 June.
Although failing to win majority support for his views in elections and referendums, Crotty continued until the end of his life his campaign against Ireland's membership of the European Union.