Ahead of their appearance at a Senate inquiry on Friday, chair of the Australian Charities and Not-for-profits Commission advisory board Robert Fitzgerald and ACNC commissioner Susan Pascoe have called on the federal government not to shut down the commission.

Mr Fitzgerald argues that the only beneficiaries of the planned abolition are organisations that ''don't want transparency'' and that it is ''impossible'' to understand the public benefit of getting rid of the body that was set up under the Gillard government in late 2012.

There have been at least seven inquiries that highlighted the need for an independent charity regulator over the past 20 years.

''The ACNC was developed based on the most robust evidence and consultation that has ever been undertaken with the not-for-profit sector sector,'' Mr Fitzgerald told Fairfax Media.

Among other duties, the commission registers charities, helps them meet their reporting obligations, investigates complaints and maintains a publicly searchable register of charities.

Mr Fitzgerald, who is also a commissioner on the royal commission into child sexual abuse, said that in its short existence, the ACNC had provided transparency to the community – that effectively funds the tax concessions for charities – and removed duplication between different compliance regimes.

''So the question is . . . why are we now looking at the possible repeal of the ACNC? And the answer to that question is almost impossible to find out,'' he said.

Ms Pascoe said it ''would seem that the case has been made'' for a national regulator.

"If you dismantle [the ACNC regime], I honestly don’t know when you get it back," she said.

She said that the government had formed its view against the ACNC in opposition and had not had any consultation with the not-for-profit sector.

When asked if she thought Social Services Minister Kevin Andrews understood what the charities commission did, Ms Pascoe said, ''I'm not sure''.

Ms Pascoe said the argument to keep the ACNC was not just about the sector, but about a place where the public can search for information on charities and a place where they can direct complaints.

She noted that often complaints about charities were not ''of the order'' that police would deal with.

In its first 16 months of operation, the ACNC received 686 complaints and concerns about charities, of which 272 were were further investigated.

The ACNC is not uniformly supported, however.

Peter Hersh, director of Logicca chartered accountants told the committee that the ACNC should be abolished as soon as possible.

He argues that it had failed to reduce red tape and that it had made it more difficult for charities to get tax deduction status.

The Financial Services Council will also argue against the charities commission at the Senate hearing, arguing it imposes costly compliance obligations that divert funds ''away from charitable purposes''.

Before the 2013 election, the Abbott government pledged to get rid of the ACNC and move its regulatory functions back into the Australian Taxation Office to ''reduce red tape''.

Fairfax Media has previously reported that Cardinal George Pell's office had lobbied the Coalition to get rid of the charities regulator.

On Thursday, Mr Andrews said the government would stand by its decision to shut down the ACNC.

''We have a view that we start from a position of trusting the charitable sector . . . and we don't think that an extra level of regulation and red tape and reporting is the answer,'' he said.

The ACNC repeal bill was introduced into federal parliament in March and is currently the subject of a Senate inquiry, due to report back by June. Friday's Senate hearing has been preceded by strong criticism from the not-for-profit sector about the ACNC abolition.

In March, about 40 of Australia's most prominent charities, including the RSPCA, Lifeline and World Vision, wrote to Prime Minister Tony Abbott, asking him to keep the ACNC.

A 2013 survey by Pro Bono Australia found that of 1500 stakeholders surveyed, about 80 per cent supported the commission.

Labor and the Greens are also opposed to the abolition.

''I just don't see why Kevin Andrews would want to open Australia's charitable donors to the risk of more scams,'' shadow assistant treasurer Andrew Leigh said.