Who needs a police certificate?
什么人申請留學簽證(學生簽、陪讀簽)需要提交無犯罪證明?
In brief: those aged 17 and over applying for temporary entry class visas who intend to stay in New Zealand for 24 months or longer;
Details: https://www.immigration.govt.nz/opsmanual/#45181.htm
简单的说,年满17岁,打算在新西兰停留24个月或更长时间的人,需要提供无犯罪证明。

详细规定见以下网址(警方证明书,就是无犯罪证明):
中文翻译:http://www.admission.nz/ym/kmslaw/45181
英文网址:https://www.immigration.govt.nz/opsmanual/#45181.htm
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