The Commission has previously said it wanted to address the "injustice" of current laws that allow trusts to be used to avoid having to share property equally when couples separate.
This afternoon's report noted that a 2002 law change intended to address the issue had proved inadequate because it only allowed income from assets held in trusts rather than the assets themselves to be used to compensate a disadvantaged partner.
Its recommended law change would allow courts to order the transfer of trust assets if those assets would have been available for division between the couple as relationship property.
Another key recommendation was that courts would be able to find that a trust had not been established and had no legal standing if the person who established it continued to manage the assets it held "as if they are their own personal property".
Sir Grant said given trusts formed a core part of New Zealand's economic, social and legal infrastructure, it was vital for the law around them to be "clear and accessible to ordinary people who use them".
The current law was "outdated and much of it is difficult to understand".
He said it was in the public interest "to have a modern statute that gives trustees and others guidance as to how a trust is to be managed and increases the accountability of trustees".