 Maher joined the Green Party in 1989 and held many positions in the party over the years – as former MEP Patricia McKenna's election campaign manager in 1999 and a member of the party's election task force from 2001 to 2004 which organised the party's 2002 general election campaign and 2004 local election campaign.On 22 January 2009, she announced her resignation from the Green Party, citing irreconcilable differences regarding policy and the direction of the party leadership.She stood as an Independent candidate at the 2009 local elections but was not re-elected.