After years of parliamentary chaos – much of it linked to Mr Shaw – Coalition strategists are desperately hoping an apology will provide "clear air", enabling the government to sell its agenda in the remaining weeks before the November 29 election.

But on Friday, Mr Shaw heavily criticised the government's decision to spend $8 billion on the East West Link, saying the Coalition had not released a "business case ... for such an expensive project".

"With no business case and mixed support on this project, the Coalition government should be taking this project to an election to establish whether this is actually what Victorians want, or simply to release the business case," he said in a statement.

Mr Shaw said the money for the project would be better spent on schools, hospitals and sporting facilities, "as well as restoring the direct link to Flinders Street for Frankston rail services", instead of an eight-kilometre stretch of road.

He added that $8 billion, if shared evenly across 88 electorates in Victoria,  "would result in over $90 million for each district".

"This significant injection of funds has the potential to greatly benefit every community throughout Victoria," Mr Shaw said.

These comments, which come only days before Mr Shaw is due to apologise, may cause issues for his return to Parliament next week.

There is no obvious mechanism for Mr Shaw to deliver the apology, which is due to take place on Tuesday as a key requirement of a suspension motion passed by Parliament in June, which also ordered him to repay $6838.

Under the rules of Parliament, the apology - technically for breaching the parliamentary code of conduct - could be delivered either as a personal explanation, through a 90-second member's statement, or if Mr Shaw were to seek leave of the House to speak.

The most likely option is that Mr Shaw will apologise through a personal explanation, although it would need to be pre-approved by speaker Christine Fyffe.

Labor strategists believe Mr Shaw's ongoing presence in the Parliament for the remaining three sitting weeks of the current term will continue to destabilise the government and grab headlines.

The balance-of-power independent's relationship with the Napthine government has all but collapsed. Mr Shaw is refusing to guarantee the government's legislative agenda and has angrily accused the government of making misleading claims that he wanted to get married overseas while on a taxpayer-funded trip and demanded judicial appointments in exchange for his support.

Some government MPs are nervous about the possibility that Mr Shaw could use his remaining time in Parliament to create further havoc, while others argue his capacity to disrupt is limited because the Coalition's legislative agenda is mostly complete.

It will be up to the Parliament collectively to determine whether Mr Shaw's apology is "appropriate" and meets the requirement of the motion against him. Any MP can propose a motion to expel Mr Shaw.

The looming apology follows a report from Parliament's privileges committee that found Mr Shaw misused his parliamentary vehicle for commercial purposes, although it could not establish that the misuse had been "wilful".

With Caroline Zielinski