Manslaughter charges dropped days before WA boat crash trial set to begin

A Greenfields father accused of killing his wife and her best friend in a boat crash has had his manslaughter charges dropped

The shock twist today came days before John Burdon's trial was due to start.

He was accused of steering into a channel marker, killing his wife and her best friend in the Mandurah Estuary, south of Perth, last January.

READ MORE: Teens accused of 60km pursuit across Sydney in white van

But almost two years later and just days before his manslaughter trial, Burdon's charges were dropped.

"He's grieving, he lost his wife, he lost his wife's best friend," Burdon's lawyer Michael Tudori said.

Prosecutors revealed new witness evidence meant the state would be unable to prove the father was driving the boat.

According to the 48-year-old's defence lawyers, it's a belated backflip, saying police were aware of these reports shortly after the tragedy.

"That's an absolute horrible thing to happen to someone who's been led to believe for the last two years that he's responsible for the death of his wife," Tudori said.

"That's not good enough."

READ MORE: Man stabbed in hand during attempted carjacking on Gold Coast

Four people were on the boat at the time of the crash - two best friends, Debbie Burdon and Kylie Bazzo, were killed after they were flung overboard. Mick Young survived unhurt.

"John was knocked unconscious, bleeding on the boat and has no recollection of what happened," his lawyer said.

Kylie Bazzo's family, including West Coast Eagles defender Rhett Bazzo, were in court to watch proceedings today.

John Burdon's defence lawyers are now exploring possible avenues for compensation but say it's not guaranteed.

DOWNLOAD THE 9NEWS APP: Stay across all the latest in breaking news, sport, politics and the weather via our news app and get notifications sent straight to your smartphone. Available on the Apple App Store and Google Play.