Exclusive: There’s a good reason Jess Rigby is working harder than ever before in an unpaid job with no days off.

The mother-of-four has taken on the role of unofficial detective investigating the death of her brother-in-law, Jason Rigby, who was found stabbed in his staff quarters at Nadi’s five-star Crowne Plaza Resort in Fiji.

 Jason Rigby, who was found stabbed in his staff quarters at Nadi’s five-star Crowne Plaza Resort in Fiji

Jason Rigby was found stabbed in his staff quarters at Nadi’s five-star Crowne Plaza Resort in Fiji (pictured) 60 Minutes

After refusing to believe the Fiji police ruling that Jason died by suicide, Jess has set about uncovering new evidence.

“Sometimes I sit in our office on a Monday or Tuesday after I drop the kids off to school and I’m like, ‘Alright, what other avenue can I do? What other? Who else can I research? Who else can I reach out to? What else can we do to make some kind of change?’

“And there is nobody doing that for Jason.”

Mother-of-four Jess Rigby (pictured) has been investigating the death of her brother-in-law

Mother-of-four Jessica Rigby (pictured) has taken on the role of unofficial and unpaid detective, determined to find answers about her brother-in-law’s death. 60 Minutes

But now, nearly two years on from Jason’s death, Jess has finally found an unlikely ally echoing her own determination.

With 30 years of investigative experience and a graduate of the FBI Academy in the US, Fiji Police Force Assistant Commissioner Loraini Seru has revealed the investigation into Jason’s death has changed from suicide to murder.

“We are determined that we’ll get the answers,” Seru said.

“We have treated it as a murder investigation.”

What’s confounding about this case is that as Jason lay dying, there were two other people in the room: his girlfriend Shivani Siwan and best friend Ian Lovie.

Siwan told police she was there when it happened and immediately called Lovie.

Lovie has always maintained Jason stabbed himself, yet he’s never spoken to the Rigby family to explain exactly what happened.

Siwan did speak to the family and it was the first they heard of Jason’s death.

But it was 10 hours after he’d been stabbed.

Jason’s girlfriend at the time, Shivani Siwan, refuses to talk

Jason’s girlfriend at the time, Shivani Siwan, refuses to talk  60 Minutes

 Executive chef Ian Lovie (pictured) was in the room as Jason Rigby died

Executive chef Ian Lovie (pictured) was in the room as Jason Rigby died  60 Minutes

“So Shivani was the person who told Jason’s parents that he had died,” Jessica said.

“All she said to Robin and Peter were, you know, ‘Jason’s gone. He came home. He got a knife, went to the bathroom, and I heard a thud. He’s gone.’

“That was essentially how we knew he’d passed.”

Police have spoken to 18 witnesses, but there’s one person police are focusing on.

Seru has named Siwan as the only suspect so far.

Assistant Commissioner of the Fijian Police, Loraini Seru (pictured) reveals that the investigation into Jason’s death has changed from suicide to murder.

Assistant Commissioner of the Fijian Police, Loraini Seru (pictured) reveals that the investigation into Jason’s death has changed from suicide to murder. 60 Minutes

Seru revealed the police brief of evidence has just been handed to Fiji’s Office of the Director of Public Prosecutions for possible charges.

It’s a huge breakthrough for Jess, but she believes there’s at least one more person who needs further police scrutiny.

Watch the full story on 60 Minutes on 9Now.

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