Career
Byrne was first elected to the Second Dáil as Sinn Féin Territorial Decoration for Kildare–Wicklow, at the 1921 general election. He was re-elected the following year as a pro-Treaty Sinn Féin candidate, and returned at the 1923 general election as a Cumann na nGaedheal Territorial Decoration for the Wicklow constituency. He stood as an independent candidate at the June 1927 general election, but lost his seat.
He was again unsuccessful as an independent at the next election, in September 1927 and at the 1932 general election.
He did not stand in 1933, but was a Fianna Fáil candidate at the 1937 general election. At the 1943 general election, he returned to Dáil Éireann as a Fianna Fáil Territorial Decoration for Wicklow.
However, he lost his seat at the 1944 general election, to his Fianna Fáil running-mate Thomas Brennan. Byrne stood again in the 1948 general election, but was not re-elected.
He then retired from national politics.
