Police are investigating the use of taxpayers' money by the Victorian Parliament's former speaker and his deputy after they both made questionable expenses claims for their seaside residences.

Victoria Police have confirmed that matters relating to both Telmo Languiller and Don Nardella had been assessed and had progressed to the "investigation stage" after they were referred in March.

"As the investigations are ongoing we will not be commenting further," a police statement said.

In February, The Age revealed that both men were claiming a lucrative second residence allowance designed for country MPs, by moving their registered homes away from the western suburbs electorates they represent to Ocean Grove and Queenscliff.