Are butterfly knives illegal in Ireland?

Yes, butterfly knives are illegal in Ireland. The Criminal Justice Act 1997 prohibits the importation, sale, or possession of any knife defined as an offensive weapon. This includes any knife that has a blade that is more than 3 inches long or that is designed or adapted to cause serious injury. Butterfly knives are specifically mentioned as examples of offensive weapons in the legislation, and anyone caught with one could face jail time and a fine.