The Independent Police Conduct Authority is investigating a complaint that police officers assaulted a 41-year-old Indian woman during an Immigration New Zealand visit to her home.
A female police officer allegedly bent the finger of Pooja Kapila, and another male officer prised her hand open and forced a thumb on to an ink pad to get her fingerprints for forms required to deport her family.
Police yesterday said they had already started their own investigation, but the independent investigation would establish whether the matter was handled appropriately.
Supporting medical documents from Bayfair Doctors said Mrs Kapila had minor bruising and swelling, decreased sensation in her fingers and "marked decreased range of movements" of her hand and wrist.
Mrs Kapila said the family had been in New Zealand for about 10 years, and intended "to stay here with my children" even if her husband was deported.