New research shows for every 100 sexual violence incidents reported to police, just six people were imprisoned - and Jan Logie says that's "not good enough".

The Green MP and Under-Secretary to the Minister of Justice launched a new report on Friday with analysis of 23,739 sexual violence cases reported to police between July 2014 and June 2018.

On top of the finding that six people were jailed for every 100 sexual violence incidents, only 31 made it to court, and 11 resulted in a conviction.

Logie said the findings "demonstrate the importance of our whole-of-Government approach to ending family violence and sexual violence".

"We have to work together, work differently and work across the whole justice system so every person harmed can get the resolution they need."

The research also found that victims of sexual violation - the most serious type of offence, including rape and unlawful sexual connection - were less likely to end in court action or a conviction.

The majority of children and young people experienced indecent assault the research found, and those cases were more likely to end in a conviction, but less likely a prison sentence.

Some positive signs shone through, including a 34 percent increase in the number of sexual violence investigations resulting in court action.

There was also a substantial decrease in the proportion of cases not classed as a crime, which the research attributed to changes following the 2004-2007 Commission of Inquiry into Police Conduct.

Launched under former Prime Minister Helen Clark, the commission carried out a full investigation into the way in which the police dealt with allegations of sexual assault by their own members and associates.

In 2017, former Police Commissioner Howard Broad released a report saying all of the recommendations made by the commission for police had been met, with improved response processes for sexual assault complaints.

"The Police have given more priority to investigating adult sexual assaults than in the past," Broad said at the time. "They monitor and review the investigations better, using a case management approach."

The 2017 report says there used to be a culture within police of "don't be silly" or "toughen up", but now training is given to senior detectives about the impact abuse has on people.

"We can already see positive results... But there is still a very long way to go," Logie said. "This Government is committed to making progress on these long-term challenges."

The researchers found that the way police appear to handle and investigate reports of sexual violence has improved.

Logie said the report highlights the Government's commitment to improving New Zealand's justice system, with legislation due to be released later this year around sexual violence laws.

It follows recommendations made by the Law Commission in March after its review of the Evidence Act 2006 - a review it's required to do every five years.

One of its recommendations was to ban questioning in court about complainant's sexual history, which the Government said it accepted in September, along with 18 of 27 other recommendations.

The Government is already progressing six of the recommendations relating to complainants and witnesses in sexual violence and family violence cases, the details which were announced in July.

Justice Minister Andrew Little said in September the Government wishes to further consider the remaining nine recommendations.

The Government announced $320 million over four years in Budget 2019 to fight family and sexual violence, $32.8 million of which is to improve the justice system's response to sexual violence victims.

The New Zealand Crime and Victims Survey estimated in 2018 that approximately 87,000 adults were the victim of around 193,000 incidents of sexual violence.

Newshub.