“Courts will have to consider a history of family violence as one of seven new criteria when new laws scrap the assumption of “equal shared responsibility” in the most significant change to parenting arrangements since 2006.

What’s in the best interests of a child will become the prime consideration in divorce cases when the controversial Howard-era legal presumption that parents have “equal shared responsibility” is abolished.

The seven factors that judges must consider – which have been simplified from the previous list of 15 – include a child’s safety, their views, the benefit of having relationships with both parents, and the child’s developmental, psychological, emotional and cultural needs.

The factors removed from the list include the lifestyle and background of a child and their parents, the attitude to parenthood demonstrated by each parent, how a change in circumstance would affect the child, and the parents’ prior efforts to spend time with the child.

Attorney-General Mark Dreyfus on Tuesday said he would move amendments that aligned with a Senate review – which called for explicitly adding the family violence condition – when the bill reaches the upper house in coming weeks.

But the most significant change will be abolishing the presumption of “equal shared parental responsibility” that separated parents have been entitled to since 2006, when it was introduced by the Howard government to address a historical bias against fathers’ custody.

It meant courts had to start with the presumption each parent gets an equal say in major decisions about their children, and included an associated provision that also required courts to consider time arrangements for children to spend with each parent.

However, the Australian Law Reform Commission found the law was being misinterpreted to mean both parents should see the child for an equal amount of time.

While Australian Institute of Family Studies research says only 3 per cent of separating families have their parenting arrangements determined by a court, the government believes the law serves as a guide to the rest of the families who negotiate their own arrangements.

Family lawyer Jodylee Bartal said Labor’s bill sought to make the first major changes to parenting provisions since the 2006 reforms.

“[The Howard-era reform] was a real shift from the days of the ‘Disneyland dad’, when the non-resident parent would typically see the child fortnightly, on weekends, sometimes in school holidays. It created a bit of a yardstick [around expectations for equal or significant time],” she said.

“These reforms are a positive change for people suffering family violence or coercive control. But for other families, the removal of that yardstick may mean there’s no starting point for engaging in negotiations.”

Bartal said the government’s intention had been to simplify the laws. “But as is often the case, simplifying things adds a bit of uncertainty. There is some concern that removing definitions broadens the potential outcome for families,” she said.

“There’s an increased potential for litigation while the kinks are being ironed out.”

Attorney-General Mark Dreyfus said when introducing the bill earlier this year that the government recognised that “for most children, it is strongly in their best interests to have a loving and nurturing relationship with both parents after separation”.

“The simplified list of best interest factors includes consideration of the benefits to children of having a relationship with each of their parents, where it is safe to do so.

“However, it is necessary to amend the law so it is clear that there is not, nor has there ever been, an entitlement for parents to spend equal time with their child after separation.”

The Senate review also called for stronger safeguards to protect parents from disclosing confidential information, such as personal health records and counselling notes, when there was no value to giving the information.

Greens Senator Larissa Waters, who championed that amendment, said she was glad the government would act to stop subpoenas being weaponised in court.

“Stakeholders have suggested that a blanket ban on access to medical or psychological records is not always helpful, so we support the department’s moves to redraft that section of the bill in a way that ensures [complexities] are taken into account,” she said.

Labor’s bill also introduces a requirement for independent children’s lawyers to meet directly with children, and for the court to consider the right of Aboriginal or Torres Strait Islander children to maintain their connection to their family, community, culture, country and language.

Senator Tammy Tyrell said she would also support the bill. “It puts the focus back on the children, and the best outcome for them. That can only be a good thing. There’s been a couple of reviews that have recommended these changes, and I’m glad they’re being acted on,” she said.

The bill should sail through the Senate with sufficient crossbench support and come into effect six months after it is passed.”