Winston Peters says the term 'woman' needs protection - by a bill legally defining it as an adult human biological female. 

MP Jenny Marcroft's proposed Members bill would legislate gender to biological sex, essentially meaning transgender people could not legally align with their identities.

The New Zealand First leader says having to write the law this way is unusual, but it has become 'critical'. 

"And the fact of the matter is - that this is a case where women, who are deserving protection and support in many other occasions, are simply not getting it in our law."

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