Declarations that fundraisers must make to the public explaining how they are paid are too complicated and "incredibly difficult for charities to get their heads around", according to Lindsay Boswell, chief executive of the Institute of Fundraising.
Boswell told a charity law conference last week that the complexities of the subject had not been addressed properly when the Charities Act 2006 was being drafted.
"The declarations are essential and the Office of the Third Sector has done a good job with its guidance," he said. "But no one can deny that if the institute has had to issue 15 draft templates for the declarations different kinds of fundraisers have to make, things must have gone dramatically wrong."
He also doubted whether the new regulations would be enforced. "The police and local authorities don't give a monkey's about what goes on in the world of fundraising," he told the conference, run by the Directory of Social Change and law firm Bates Wells & Braithwaite.
Boswell also questioned whether the part of the Charities Act transferring the licensing of public collections to the Charity Commission would be implemented. He said: "The proposals are fantastic, but the Charity Commission doesn't want to have to issue public collections licences because it doesn't have the resources. And if you asked the OTS legal team where public collections are in its priority list, it would probably say '12'".
Mick Aldridge, chief executive of the Public Fundraising Regulatory Association, told Third Sector it was understandable that the OTS had other priorities, such as compensating charities for losses in the Icelandic banking collapse.
But predictions from senior sector pundits that the measures on public collections would never be brought in could become self-fulfilling prophesies, he said.
A spokesman for the OTS said: "We are carrying out research that will inform the implementation of the licensing regime. This is a sensible approach and should not be taken to mean anything else."