She was briefly a member of Seanad Éireann, the upper house of the Irish parliament, and, for several years, of Dublin City Council, which, in a very rare move, removed her for non-attendance.
This was finally accepted by the Blood Transfusion Service Board and women infected in 1991 were acknowledged as recipients and received treatment and compensation.
Cosgrave was the first woman to go public about the failings of the BTSB, allowed herself to be photographed by The Irish Times, and contributed to the writing of a book Hep C, Niamh’s Story by Fergal Bowers.
[7] In June 2006, it was revealed that Cosgrave had the worst attendance record of any city councillor, with presence at just 17 out of 33 meetings over the preceding two years.
[8] In September 2007, she was deemed to have resigned her membership of the council for non-attendance, and expelled, having attended no meetings for six months;[9] she was replaced by a co-opted fellow Fine Gael member, Pat Crimmins, who later won election.