John Lahart is an Irish Fianna Fáil politician who has been a Teachta Dála (TD) for the Dublin South-West constituency since the 2016 general election.He was a member of South Dublin County Council from 1999 to 2016.
He unsuccessfully contested the Dublin South-West by-election in October 2014.A graduate of Mater Dei Institute of Education qualifying as a post-primary teacher in 1988, Lahart also received a master's degree from Mater Dei in 1996. He was appointed to the Fianna Fáil Front Bench by the Leader of the Opposition Micheál Martin as Opposition Spokesperson for Dublin in May 2016.