National is looking for new friends to support a ban on children under 16 using social media.
The party has put a member's bill into the ballot which could see New Zealand follow in Australia's footsteps.
But coalition partner ACT says the proposal is hastily drafted, simplistic and unworkable.
Online law expert Judge David Harvey said it would breach the Bill of Rights Act, a claim denied by the bill's sponsor, National MP Catherine Wedd.
If it became law it would empower parents, she said.
Judge Harvey said the breach would occur because of the right to freedom of expression.
"They [Under 16s] would be basically offline as far as that means of communication is concerned, remembering of course that the internet is primarily a system for communication so any attempt to regulate the internet has implications for freedom of expression."
He said some of the social media harms, such as cyberbullying, concerns over body image, anxiety and depression, did not apply to all youngsters.
It was possible that some, perhaps through "a lack of resilience" or "difficulties to adjusting" in messaging, "suffer some sort of problem as far as social media is concerned".
But it was an issue that should be dealt with by their families.
He pointed out the irony that on the same day the bill was announced, the Censor's office released a report on harmful digital content.
The Censor had pointed out that young people were finding it difficult to share their concerns about online content with someone else.
"And what the Censor suggests is there should be an opportunity for educating parents ....so that kids can feel comfortable going to their parents to say 'look I've got a problem'."
The state shouldn't be taking over the role of parents, he said.
"Do you want the government to solve every problem?"
Nor did the retired judge agree that the internet platforms were using algorithms to make their content addictive.
He said people needed to be careful using that word, he preferred to call it "habit-forming".
Young people were communicating with their constant use of their phones, and it was part of a dramatic change brought about by digital technology.
"That's the way they live their lives."
'It's empowering parents'
MP Catherine Wedd who is behind the bill said it didn't breach the Bill of Rights, as claimed by Judge Harvey.
As a mother of four, she was "living and breathing the negative impacts of social media in our communities every day".
Parents were "grappling and struggling" to combat its negative aspects and the government needed to do more to support them.
Parents and principals were regularly complaining about its harm, which included cyber bullying, inappropriate content being shared, exploitation and its impact on mental health.
"We have restrictions in the physical world to protect our kids, we should have them in the online world as well."
Asked if it restricted the freedom of expression of those under 16, she said the main responsibility was to protect them from harm.
As for encroaching on parental responsibility, "responsible parents can't necessarily control what is being served up to their kids by the social media companies, what's being shared online by others ...", Wedd said.
"We're taking a responsibility .... It's giving more control to parents, it's empowering parents, it's creating a level playing field for parents."
Regarding controls on gaming sites, Wedd said her bill mirrored what was being proposed in Australia, so it would target platforms such as Facebook, Instagram, X (formerly Twitter), TikTok and Snapchat.
"These are the traditional platforms where we are seeing kids and we are seeing a lot of the online harm caused by these platforms."
The need for restrictions to gaming sites access would need to be explored.
Asked about not getting support from ACT, she said it was a complex issue that she had been working on for over a year and she had the support of the National caucus, including the prime minister.