[4] In 2005, Boylan moved to County Kerry while working as a coordinator for the Irish Wildlife Trust at Killarney National Park.

Under her Irish-language name Lynn Ní Bhaoighealláin,[5] she stood at the 2007 general election as the Sinn Féin candidate in the Kerry South constituency.

[7] In September 2013, Boylan was selected as the Sinn Féin candidate for the Dublin constituency at the 2014 European Parliament election.

[6] As the election count pointed towards Boylan's win, the Fianna Fáil candidate Mary Fitzpatrick asked: "Who could have said somebody would come from nowhere, no track record in Dublin, and still take the lead and steal the first seat and probably have a surplus?".

[7] Boylan was a campaigner[10] for the release of Ibrahim Halawa, an Irish citizen from Firhouse in South Dublin who was imprisoned in Egypt between 2013 and 2017[11] and was adopted by Amnesty International as a prisoner of conscience.

[12] In March 2015, Boylan described Halawa as an "Irish-speaking, GAA-playing Dublin lad", and asked if the Irish Government would do more if his name was "Paddy Murphy".