"It's negative, blaming the victims," Prof Shannon added.
Prof Shannon, of the university department of social work and community development, said that if the Government genuinely wanted change, it would help create more work, rather than cutting benefits.
The Government announced this week it would introduce sanctions such as benefit cuts for those who did not genuinely attempt to find or train for work, and more rigorous assessments of sickness beneficiaries by shortening the period between medical checks.
Part-time work obligations would also be extended to domestic purposes beneficiaries with children over the age of 6.
Prof Shannon said some policy change moves, such as giving Social Development Ministry case managers the power to impose sanctions including a 50% benefit cut for long-term beneficiaries failing to undertake work test requirements, would further undermine trust between people needing support and those who were employed to provide it.
He predicted growing demand for foodbanks.
It was ironic that politicians, who themselves enjoyed many taxpayer-funded benefits, were effectively reducing benefit access for much poorer groups of people.
There was a popular misconception that people remained on the domestic purposes benefit for many years, but its average use was, in fact, only for about three years, he said.
New Zealand had one of the worst child poverty rates among OECD countries.
"We need to look after and care for children.
"We treat children very, very badly in New Zealand," he said.
A reassurance from Government that beneficiaries with children could not have their benefits cut by more than 50% was a "ridiculous statement".
In the long term, New Zealanders were paying a heavy price for child poverty, including through worse educational achievement, and subsequent crime and other social problems.
The policy changes were "very politically motivated" and flew in the face of well-established research about what was needed to reduce child poverty and to support disadvantaged families.
Many of the policy changes were "incredibly self-defeating".
"They're just going to worsen the situation."
