(Bloomberg) — New Zealand Prime Minister Jacinda Ardern’s leadership is under scrutiny after her Labour Party botched its handling of an alleged sexual assault on a 19-year-old party volunteer.Ardern has been forced to apologize to the woman and take control of an investigation into the allegations, including that she was attacked and groped by a Labour Party staffer in early 2018. The party decided earlier this year that no disciplinary action was necessary, prompting the woman to tell her story to the media. Since then, Labour Party President Nigel Haworth and the man at the center of the allegations, who worked in parliament and hasn’t been identified, have both resigned.“There are no excuses for the handling of the complaints by the Labour Party, and I will offer none,” Ardern said at a post-cabinet press conference in Wellington on Monday, a week after the sexual assault allegation was detailed by website The Spinoff. “We have a duty of care, and we failed in it.”A year out from a general election, the scandal has the potential to undermine support for Labour and Ardern, whose popularity has much to do with her image as a caring leader and champion of the disadvantaged, including women in the workplace. Questions are being asked not only about the culture of the Labour Party, which mishandled a separate sexual assault allegation last year, but also whether Ardern knew about the allegations sooner than she says she did.The Labour Party looked into multiple complaints against the man from several people, including harassment and bullying, but Ardern says she was not aware of the sexual assault claim until The Spinoff article.While Haworth said the woman’s complaint about the man didn’t include the allegation of sexual assault, she insists it did. A lawyer is currently conducting an appeal process, and Ardern said today that an independent third party would review Labour’s handling of the allegations. Ardern has also agreed to meet with the complainants.“While the party has continued to maintain that they weren’t in receipt of the complaints that have since been published in the media, that is secondary to the fact that the complaints made to the party were of significant concern and needed to be heard in a timely way,” she said. “That didn’t happen.”To contact the reporter on this story: Matthew Brockett in Wellington at [email protected] contact the editors responsible for this story: Matthew Brockett at [email protected], Edward JohnsonFor more articles like this, please visit us at bloomberg.com©2019 Bloomberg L.P.