Phil Walker, a concerned citizen who says he is not a member of any political party, made a report at North Sydney Police Station earlier this month about Felicity Wilson, the new state MP for the seat of North Shore.

Ms Wilson recently admitted she signed an incorrect statutory declaration in the preselection race for that plum Liberal seat after Fairfax Media revealed inconsistencies in claims about her residential history.

But Mr Walker says he was since told that police would not investigate a possible breach of the Oaths Act 1900 because the form the MP signed included a typographical error when recounting the legislation's date.

"There is no Oaths Act 1990," Mr Walker said he was told. "It's on the wrong form therefore we don't have to investigate it."

Mr Walker is a retired builder from Mona Vale who says he was moved to act by the memory of a case he was involved in decades ago where charges were dropped against a local councillor who had embellished qualifications on nomination forms.

"I've never forgotten that," he said. "Politicians have to tell the truth."

Ms Wilson claimed to have lived in the electorate for 10 years on her nomination form for the seat, a form that was also labelled a statutory declaration.

The electoral roll and internal Liberal party records variously linked Ms Wilson to addresses in the eastern suburbs and Lindfield at points across five of the past 12 years, with another three not accounted for.

Ms Wilson undertook to submit a fresh declaration to the party following questions from Fairfax Media. "At the time of writing my nomination form I believed it to be true," she told Fairfax Media at the time. "However, upon further reflection I have since realised that figure is not accurate."

Mr Walker says he provided police with a copy of Ms Wilson's statutory declaration and relevant references for the electoral roll.

A spokeswoman for the NSW Police said the documentation it had seen was not a statutory declaration under the Act and it had no evidence of an offence.

Late last week Mr Walker lodged another complaint, this time making a virtue of the typo and asking police to investigate whether the nomination form was a document purporting to be an affidavit, another potential breach of the Act.

Making a false statutory declaration can carry serious penalties and is legally tantamount to perjury.

But Professor Alex Steel from the UNSW Law School has told Fairfax Media that prosecution of such offences is complicated by a requirement to prove that inaccurate information was provided deliberately and with the knowledge it was wrong to do so.