[2] Leahy has competed in eight Paralympic Games across boccia and athletics winning a total of eight medals.

[4] In the 1988 Summer Paralympics he won a silver in the shot put and a bronze in the club throw.

They lost to the South Korean team in the bronze medal match, so the Irish time originally finished in fourth place.

[9] In the mixed team C1-C2 competition, Ireland completed pool play with a record of 3–2 and did not advance to the semifinals.

[10] In the C2 mixed individual boccia event, Leahy advanced past the preliminary round pool with a 4–1 record.

He originally placed second in discus with a throw of 16.05 metres,[13] but was promoted to a gold medal finish when Polish Paralympian Robert Jachimowicz was disqualified for being entered in the wrong class.

He was eliminated in the preliminaries and did not advance to the quarterfinals after his performance in Group B. Leahy lost to Dan Bentley and Risa Kainuma on the first day of competition and defeated Fernando Ferreira on the second, finishing with a 1–2 record.

[20][21] Leahy competed in the BC1-2 boccia mixed team event in the 2012 Paralympic Games.