He was educated at the
Abbey Christian Brothers' Grammar School,
Newry. He graduated from
Queen's University Belfast in 1961 with a first class honours BA in History, Cosgrove was understood to be fluent in Irish but considered that the exam required by legislation passed in 1929 to be inappropriate in 2007. The Legal Practitioners (Irish Language) Act 2008 was enacted following his action, which provided for a system for barristers and solicitors to learn Irish as part of their studies. ==References==