Clergy Abused Network chair Bob O'Toole has backed Prime Minister Scott Morrison's threats to cut public funding and tax concessions from religious and other institutions that fail to join the national child abuse redress scheme.
Mr Morrison on Monday reiterated comments he made in a letter sent to 25 intuitions last week that they would be "doubling down" on the crime of child abuse if they did not sign up to the scheme by a deadline today.
The government is set to name those who haven't when it announces what action will be taken against them on Wednesday.
"Privileges that they enjoy should be taken from them if they don't comply," Mr O'Toole said.
"There are people who have fallen through the net; they need redress, they need counselling and continual support.
"If the institution is still functioning, some aren't of course, but the ones who are should be a party to it. If they're not, stick it to them."
Newcastle MP Sharon Claydon said the government needed to "back up its tough talk with action" as the joint select committee on implementation of the scheme, of which she is deputy chair, had recommended in April that the government require written statements from recalcitrant organisations outlining their reasons for not joining, along with a list of all financial benefits from public sources and derived from being a charity.
"The government should have then published a list of these organisations and their letters ... a week before the 30 June deadline," she said.
"Frankly it's not good enough for the Prime Minister to be shaking his fist at the sky one day before deadline, when his government has had more than two years to come up with a clear plan of action."
The deadline comes as an online film series is released celebrating Australian women, including former Herald journalist Joanne McCarthy, who helped prompt the Royal Commission into Institutional Responses to Child Sexual Abuse.
The project is based on research led by associate professor Katie Wright, who is investigating the role of citizen activism in relation to the Royal Commission and how collective action culminated in the inquiry.
"In America it was a searing investigation by the Boston Globe that exposed the shocking reality of institutional child abuse," Ms Wright said.
"In Australia it was the extraordinary and sustained activism of ordinary people from suburbs and regional communities - people like Chrissie, Leonie and Joanne - that unearthed our own dark history."