NSW is one step closer to requiring people to actively seek consent as an amended bill seeking to reform sexual consent laws is returned to the lower house.
Debate on whether people with mental health conditions should be required to actively seek consent continued on Friday.
The draft law created a requirement of "affirmative consent" - meaning people have to say or do something to find out whether their partner consents to a sexual activity, or they could be guilty of sexual assault.
The bill says the affirmative consent requirement does not apply if a person accused of sexual assault was suffering from a cognitive or mental health impairment at the time, if that was a cause of the failure to get consent.
They would still have to believe the other person was consenting.
Attorney-General Mark Speakman on Thursday evening said the definitions were developed with forensic mental health experts and consistent with other criminal laws.
"This is not a 'get out of jail free' card - an offender with a cognitive impairment or mental health impairment can still be convicted if all elements of the case are established beyond reasonable doubt," Mr Speakman said.
Labor, the Greens and One Nation pushed for changes to the exception, which was debated in the upper house on Friday.
A Greens amendment would have tweaked the bill to provide that the impairment must be "the" cause - rather than "a" cause - of the failure to seek consent.
Labor was successful in amending the bill to say instead it must be a "substantial cause".
One Nation MP Mark Latham wanted an amendment requiring a person to show they have a "substantial" cognitive impairment before they could fall within the exception.
He argued "more and more conditions" are being regarded as mental illnesses and "you'd have to be worried about a provision that will allow rapists and those engaged in sexual assault to get off the hook because they have a so-called mental health impairment".
Mr Latham says he found "quite compelling" a submission from frontline organisation Rape & Domestic Violence Services Australia criticising the bill's exception and warning it is too broad.
The section would be used "as a loophole for accused persons to avoid the requirement to take steps to establish consent" if the bill is passed, RDVSA CEO Hayley Foster wrote to MPs this week.
Other organisations including Domestic Violence NSW, ACON and the Older Women's Network also signed the letter.
Ms Foster told AAP she was surprised to see the bill didn't require an accused to prove they had a "substantial cognitive impairment" to fall within the exception.
There are already protections in the criminal justice system for people with mental health problems, she said.
"There shouldn't be additional protections for people who are accused of sexual assault than (there are) for other crimes," Ms Foster said.
Earlier in Friday's debate Liberal MLC Natalie Ward disputed a number of claims about the bill made by Mr Latham, who said "millions of long-term, loving couples" would be trapped by a bill that did not allow for "natural" or "spontaneous" sexual activity.
"Consent must be present throughout every sexual encounter no matter the relationship between the adults participating. This is true of the current law and the bill does not change this."
Mr Latham then moved an amendment on Friday that he said would seek to "provide clarity" on what the bill "actually means".
His proposed amendments were all voted down or withdrawn, as were a number of proposed amendments from the opposition and the Greens.
Two amendments however have been made to the bill, which is now on its way back to the lower house for a third reading.
The amendments include the Labor's "substantial cause" change and an amendment defining the terms and deadlines for a review of the laws.
Parliament sits again on Tuesday next week.
