AN Independent Commissioner Against Corruption (ICAC) investigation into the pollies perks scandal which saw local MP Stephan Knoll resign from cabinet has been stalled amid questions over parliamentary privilege.

Following the Country Members Travel Allowance scandal, which saw regional MPs repay more than $100,000 in public money last month and three government ministers resign, ICAC Bruce Lander announced his office would be looking into how the scheme was claimed across the past decade.

Amidst the scandal, former lower house speaker Vincent Tarzia released 10-years-worth of travel claim forms for the allowance, which are the subject of ICAC’s investigation.

In a rare public statement last week though, Mr Lander said the investigation had been delayed due to MPs refusing to hand over information they believe may be covered by parliamentary privilege.

“Although I am continuing to seek evidence and information from other persons and sources, the potential for a claim for parliamentary privilege has had the effect of delaying the investigation because I have not been able to examine documents and other evidence in the custody of the members and their staff, relevant to the matters under investigation,” he said.

“Also I have not been able to interview or examine the members or their staff.”

Parliamentary privilege are laws which give parliamentarians certain immunities from prosecution and investigation for matters which relate to the parliament.

Whether the documents Mr Lander is seeking come under this privilege is up to the parliament, which is currently on winter recess until September 8.

This date is after Mr Lander finishes his term as the ICAC, with future commissioner Ann Vanstone to decide whether the investigation should continue.

Speaking on Friday, Premier Steven Marshall said the ICAC legislation was “very clear” and expected all MPs to follow it.

“All members of parliament, past and current, need to comply with the strict legislative requirement,” he said.

“Privilege is something which is determined by the parliament itself.

“The legislation which covers ICAC is really clear and we also know it has elements which contain issues of confidentiality, so I don’t know about the investigation which is currently underway.”

Opposition leader Peter Malinauskas said he has instructed Labor MPs subject to the investigation to hand over any documents requested by ICAC, and would sanction anyone who declined.

“Labor MPs have complied with commissioner Lander’s request in regards to information on the country members allowance investigation,” he said.

“If they hadn’t I would have instructed them to and if they failed to comply with that instruction I would issue a sanction from the parliamentary Labor party”.