"A 2019 report showed that 42 per cent of trans and gender diverse people had reported that police knew their correct gender and pronouns but refused to use them," Blackwood said.
"Nine per cent of those that interacted with police had either been verbally or physically harassed."
Counties Manukau District Commander Superintendent Shanan Gray declined to be interviewed, but noted that "respect and valuing identity are two of our core values."
He also said the woman's pronouns had been updated within the national intelligence application.
But Blackwood said in order to prevent future incidents, police needed to enforce explicit rules.
"It's really important that police develop and implement policy that ensures correct names and pronouns are always used.
"We all have the right to be free from discrimination and treated with fairness and respect."
Blackwood said they had heard similar complaints before, and that the Human Rights Commission was very concerned that transphobia could be a systemic issue.
But they said it was up to the police to consider how they responded to the problem.
- RNZ