Grace Millane murder trial: White Ribbon calls for changes to justice system

Anti-violence charity White Ribbon is calling for changes to the justice system in the wake of the Grace Millane trial.

They're concerned about victim-blaming and fear it'll stop people who have been abused from coming forward.

Blaming Grace was never part of the Defence's plan.

"There will be at no time any blame attributed to Ms Millane or any suggestion of blame," Defence lawyer Ron Mansfield said in court.

But after calling on evidence from previous boyfriends and analysing her sexual history, White Ribbon isn't so convinced.

"There's nothing worse than seeing elements of a rape culture within New Zealand where we say 'well you were out drinking so you must have asked for it'. That is part of a rape culture," manager Rob McCann says.

McCann says the 'rough sex gone wrong' defence is incredibly concerning because the killer is the only person who knows what happened in the final moments of Millane's life.

His version of events was also littered with lies.

"Trying to claim what can be seen as normal sexual behaviour in some circles means they're less deserving as a person and that's really unacceptable," McCann says.

Criminal law expert Kylee Quince argues the Defence had no choice but to explore Millane's past.

She says it was highly relevant to the complex legal questions being asked within the trial.

"If you don't have prior sexual partner history it's particularly difficult to talk about consent if you don't have that partner there, so it's inherently a difficult problem," she says.

The arguments put in the Grace Millane trial will no doubt be the subject of legal discussion for many years.