The former Sebastopol Technical School and St Francis Xavier College pupil was bludgeoned to death in the garage of his Ahern Road, Pakenham home on New Year's Eve in 2005.

At the time, police reports said 45-year-old Mr Griffey suffered traumatic head injuries, beaten to death with a blunt metal object on the afternoon of December 29.

His body, covered in a tarpaulin and striped bed sheet, lay undiscovered for four days in his Pakenham garage. His family held a New Year's Eve party at the property seemingly without being aware of his absence, until his wife and daughter entered the space and noticed a "pungent odour".

Mr Griffey grew up with family in Ballarat and worked at the former Bakery Hill Tavern. He met his wife Diane in the city, and the couple moved to Melbourne in 1990. They ran a company, D&M Plaster Transport, together and had started a new business, Metro and Pakenham limousine service. Supporters of local sports clubs and charities, Michael Griffey was known to pick up the Pakenham under-12 cricket side he coached in a limousine.

However the businesses were in financial straits. His transport company owed $1m in taxes and $100,000 to other creditors. Mr Griffey had two life insurance policies, valued at $1.5 million.

Victoria Police spokesperson Nat Webster says the investigation into Mr Griffey's murder is ongoing.

"The investigation remains open and detectives will review any new information provided to them about the incident," Ms Webster said.

"As with many incidents of this nature, over time circumstances may change and someone with information about Michael's death may now be in a position to come forward."

Mr Griffey's wife Diane was charged with his murder in 2007. The charges were dropped after the prosecutor found the evidence would not sustain a conviction. Mr Griffey's son Kenny was also questioned by detectives but was not charged.

In 2008 Mr Griffey's mother Noela Antonio told The Courier she was heartbroken, and longed for answers.

"I know one day Michael's killer will be found," Ms Antonio said.

"I'm just keeping my fingers crossed. I just know they (the police) will do their job. I have to have faith."

Ms Antonio died in 2017.

A coronial inquest into Mr Griffey's death was announced in 2012; however it has not been held and no date for commencement has been set, despite police handing a brief of evidence to the Coroner.

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