Green Party co-leader James Shaw is taking responsibility for a speech he gave in May in which he mistakenly said that Golriz Ghahraman had worked as a prosecutor at UN tribunals for Rwanda and the former Yugoslavia.
The admission is the latest in a week in which Ghahraman's work history and how it has been presented is under intense scrutiny.
Ghahraman worked in the defence team as an unpaid intern at the Rwanda Tribunal for Joseph Nzirorera, who died before he could be convicted of genocide, and in a paid position representing pop singer Simon Bikindi, who was convicted for incitement to genocide.