"Health professionals, religious leaders and human rights advocates here and overseas have spoken out against these practices as harmful and having the potential to perpetuate prejudice, discrimination and abuse towards members of rainbow communities."
Following years of advocacy, by groups such as Ending Conversion Therapy, Labour had campaigned on banning the practice and make it a criminal offence to advertise, offer or perform it, ahead of last year's election.
Activist groups reignited the conversation in February, and Green Party MP rainbow spokeswoman Elizabeth Kerekere launched a petition in February accumulating 157,764 signatures in a matter of days.
Kerekere said she welcomed the bill, and would work with Faafoi to ensure the legislation was "robust and protects all members of the rainbow community who have suffered from these practices, including anyone who is trans, intersex or non-binary".
"We also acknowledge that conversion therapy happens to other communities, in particular to people with disabilities.
"Aotearoa should be a place where no matter who you love or how you identify, you are accepted, and no one should be allowed to force people to change who they are."
National leader Judith Collins previously said her party would support a ban after she talked to its youth wing and googled the issue.
Te Pāti Māori co-leader Debbie Ngarewa-Packer said te ao Māori (Māori world) had always celebrated diverse gender and sexual identities and "wholeheartedly" supported the bill.
It was also a step towards addressing the "dire state of our mental health system in Aotearoa", she said.
A spokeswoman for the Act Party said the caucus hadn't had a chance to discuss the bill yet and would do so at their meeting on Tuesday.
The bill creates two new criminal offences for either the most serious cases of harm or where there is heightened risk of harm. The bill also creates a pathway for civil redress.
Under the bill, it will be an offence to perform conversion practices on a child or young person aged under 18, or on someone with impaired decision-making capacity. Such offences would be subject to up to three years imprisonment.
It would also be an offence to perform conversion practices on anyone – irrespective of age – where the practices have caused serious harm, and would carry up to five years imprisonment.
Civil redress will also be an option where complaints about conversion practices could be made to the Human Rights Commission and the Human Rights Review Tribunal.
To be considered a conversion practice under the bill, a practice must be "directed towards someone because of their sexual orientation, gender identity, or gender expression", and "be performed with the intention of changing or suppressing their sexual orientation, gender identity, or gender expression".
Faafoi said the definition of conversion practice would ensure health practitioners providing health services would not be captured, nor will people providing legitimate counselling, support and advice.
"General expressions of religious beliefs or principles about sexuality and gender will also not be captured," Faafoi said.
The legislation was similar to laws introduced in the United States, Canada, Germany, the United Kingdom, and the Australian states of Queensland, Victoria and the Australian Capital Territory, Faafoi said.
After its first reading in Parliament, the bill will go to the Justice Select Committee for public submissions.
