Prime Minister Julia Gillard's former boyfriend Bruce Wilson has been urged to release files held by several law firms in relation to alleged fraud.
Ralph Blewitt made the call on Monday, saying he was a former sidekick to Mr Wilson, who is accused of using the Australian Workers' Union Workplace Reform Association to defraud the union.
Ms Gillard was then a lawyer with Slater & Gordon and advised the two officials on the establishment of the association.
She has denied any wrongdoing or that she knew of any fraudulent behaviour.
Mr Wilson has also said Ms Gillard is innocent of any wrongdoing.
Mr Blewitt told ABC TV on Monday he returned from overseas last week after a man offered to pay for his flights and expenses so he could give information on the matter.
Mr Blewitt says he has given Victorian police a dossier of files that connect Ms Gillard to the establishment of the AWU Workplace Reform Association and "other matters".
He would not comment on the "other matters".
"I've stuck my neck out here and I don't intend to make public information I've given to the police," Mr Blewitt said.
Mr Blewitt says Mr Wilson should back up his claim about Ms Gillard's innocence by waiving legal privilege.
"If you are so certain, Mr Wilson, that she has nothing to answer then you should immediately release Nick Styant-Browne, Slater & Gordon and another law firm Maurice Blackburn of client privilege confidentiality," he said.
"Notify them that you wish to allow them to release any documents or files that they have."
Mr Blewitt denied any personal vendetta against Ms Gillard.
He said he had requested immunity from prosecution before agreeing to hand over information because he was a party to fraud although he did not financially gain from it.
Former industrial lawyer Harry Nowicki, who is writing a book about the union's history, paid Mr Blewitt's expenses so he could return to Australia.
"All it is for me is an air fare and a few nights' accommodation. That's not serious money," Mr Blewitt said.