Ms Mullins became the face of a national push to strengthen sexual consent laws, after telling the ABC how she was sexually assaulted as an 18-year-old virgin behind a nightclub in 2013 by a man she'd met minutes earlier.

Two trials and two appeals later, a judge found the man involved had no reasonable basis for believing she had not consented while acknowledging that Ms Mullins - in her own mind - had not consented.

Within 24 hours of Ms Mullins' interview airing in 2018, Attorney-General Mark Speakman referred the laws to the NSW Law Reform Commission for a review.

Now, NSW will lead the country with a radical overhaul of sexual consent laws that will make it easier to successfully prosecute offenders.

The reforms announced by Mr Speakman on Tuesday mean accused rapists would only be able to prove sex was consensual if they took active steps to obtain consent.

"It's a matter of common human decency. It's about time the law caught up," he said.

The reforms went further than those recommended in the Law Commission review's 270-page report into delivered last September.

Under the new legislation, which is hoped to be in place by the end of the year, the accused will have to have done something or said something reasonable in the circumstances to ascertain consent.

It will simplify and clarify current laws in several ways, Mr Speakman says.

"Consent is something that is given voluntarily by agreement ... it can be withdrawn ... consent to one sexual activity is not consent to any other sexual activity. Self intoxication of the accused is not an excuse for failing to form a reasonable belief," Mr Speakman said.

The development will bring a major shake-up to laws which currently allow defendants to argue there were reasonable grounds to believe they had consent - even if the alleged victim did not actually consent.

That defence allowed Kings Cross nightclub owner's son Luke Lazarus to be acquitted of the sexual assault of Ms Mullins in 2017.

An emotional Ms Mullins stood alongside Mr Speakman as he announced the change.

The reforms will shut a "massive loophole" and would have absolutely changed the outcome of her case, she says.

"In 2017 I walked out of court feeling lost, alone and powerless."

"Four years of my life culminating in one word; 'dismissed'.

"I didn't consent. The court acknowledged that I wasn't consenting, and yet somehow that wasn't enough."

Ms Mullins is now director of advocacy at Rape and Sexual Assault Research and Advocacy, which says anything short of an affirmative requirement would be out of step with community expectations and put women at risk.

Ms Mullins said she was proud her case had been the catalyst for change.

"I can never go back and change the outcome of my case, but we have changed how some stories will end."

RASARA's executive director Rachael Burgin says the reform will see NSW leading the way in Australia and internationally.

The change would shift focus away from the actions of the victim-survivor and onto those of the accused.

"No longer will perpetrators be able to rely on rape myths and stereotypes to argue that the unrelated actions of the victim-survivor 'implied' that they were consenting," Mr Burgin said.

"People who act without doing or saying something to make sure they have consent will be culpable."

However, the NSW Bar Association says the laws will potentially criminalise many consensual sexual relations.

The new definition - which states consent for one sexual act doesn't imply consent for another - is also problematic, it says.

"In other words, every single sexual touching and act in the course of a physical liaison will need positive consent in order to avoid criminalisation," president Michael McHugh said.

"This too has significant ramifications in criminalising conduct within, in particular, established respectful relationships."

But Mr Speakman says the reforms require the application of common sense, and the protections of procedural fairness for an accused remain in place.

Shine Lawyers and an array of domestic violence services and advocates in NSW also say it is a win.

Both NSW Police Commissioner Michael Fuller and Mr Speakman are confident the reform will lead to wider behavioural change in society.

The law reform commission found that sexual offences are under-reported, under-charged, under-prosecuted and result in a lower proportion of convictions than other offences.

Australian Associated Press