When they tried to arrest Murray Hearne, Peter wound up dead, Jason critically injured, and Hearne went on the run.
Jason rarely speaks of the night his mate tried to save him and wound up collapsed on top of him, stabbed, never to see his beloved wife Jackie and children Mitchell and Brodie again.
All speak at length of the night Murray Hearne turned cop killer, and of the painful nights ever since, on Channel Seven's Murder Uncovered tonight.
"You can't plan for this .... I miss him", says Peter's widow, Jackie Reimer, wiping tears as she relives that night.
Watching back old videos of Peter with their children gives her a "physical pain. It hurts in my chest. It's a real pain, it's not just a feeling."
Peter's daughter, Brodie now 20, acutely feels the absence of a man she loves, but never knew.
"I feel like I know so much about Mum. I can tell when I walk in if she's had a good day or a bad day, she doesn't need to tell me," Brodie says.
"And then I don't know one thing about Dad.
"I don't know how he carries himself. I don't know his sense of humour. I don't know ... just the little things you should know about your dad. I don't know those."
THAT NIGHT
Jason Semple is a mountain of a man - of a size that if he told you to get stuffed, you'd probably start making arrangements.
A man not easily given to tears. A man, who, when Hearne stabbed him, didn't feel the knife. "It felt like a soft punch," he says.
But on February 28, 1998, he was the new kid on the block - "the full rookie" invited by Peter with another officer, Brian Neville, for a few post-work 'welcome drinks' in Sydney's inner-city Ultimo, not far from where Peter lived.
"It wasn't meant to be a last catch-up," says Brian, fighting tears..
The trio had finished at the pub and were walking along Harris Street when a young male in a group of four yelled "do you want some E's?" (the drug, Ecstasy).
Suddenly, three off-duty cops were on duty.
Realising Murray Hearne was the one with the product, called him over to them asking to see the drugs. Then they grabbed him and walked him down the road, to search him.
When Hearne rose out of a crouch, the night took a fatal turn.
"I felt a couple of blows ... first to my chest and stomach ... but I thought I was getting punched," Jason remembers.
"It felt like weak punches ... like 'is that all you've got?'."
Hearne made a break and bolted. Jason felt like he was "leaking", lifted his shorts, and realised he'd been stabbed.
As Brian went in pursuit of Hearne, Jason watched blood spray from his stomach.
Peter came to his aid, laid him in the gutter, started shouting for help.
'NOBODY KNEW HE'D BEEN STABBED'
"Peter was calm, he was single-minded on getting me help. ... Pete was so normal, nothing to indicate he'd been injured," says Jason.
"Nobody knew he'd been stabbed. Least of all him."
Until Peter collapsed onto Jason's chest.
"Pete's talking to me, then next thing he's basically laying on top of me ... it was like he'd just fainted on top of me ... I remember looking down watching the blood, thinking 'what's wrong with Peter?'," says Jason.
The tears come.
"And the last thing he ever says to anyone on earth is 'she'll be right mate'."
Peter was stabbed twice in the heart. Jason was taken to hospital and surgery.
Peter was pronounced dead not long after midnight.
And Hearne was on the run.
THE HUNT
Initially, police had no idea who the cop killer was that they were hunting for.
But Hearne couldn't resist bragging to friends. Within 24 hours they had a name, and two properties under surveillance. Now they needed evidence, or a confession. Preferably both.
By Monday, they'd spotted him, and had his phone intercepted, and had to endure listening to him watch a news report about the injured Jason.
As he watched, Hearne told someone he was on the phone to: "that's the big c*** ... that's him ... I dropped him on his arse".
When the story of the hunt appeared that night on the TV show Australia's Most Wanted, the crack came.
His own stepfather contacts police: "I'm nervous. because it's one of my kids that did it," he said. "His name is Murray Hearne".
Arresting officers tell Murder Uncovered Hearne cried when he was caught. And he wet himself.
Meanwhile, those that loved Peter, buried him.
Jason was told he was too sick to attend. He went anyway, ditching the wheelchair and walking into the service.
Jackie tried to keep it together for the children.
"My time for me was late in the middle of the night, when nobody else was around," she says.
"I had to hold it together and pretend that I was strong (for the kids), but I was only pretending. I wasn't strong," she says.
FACE TO FACE WITH A KILLER
Jackie wanted answers, and hoped Hearne's trial would give them.
Until he changed his plea the morning it was to start, pleading guilty to the murder of Peter Forsyth, and to a lesser charge for stabbing Jason.
"I was shocked and disappointed all over again," she says. "I was 'you're not going to say anything ... you're not going to tell me anything. I've got nothing again now. Nothing."
Hearne was sentenced to 27 years jail. It was reduced on appeal.
Another blow to those grieving Peter.
From jail Hearne asked to see Jason. Jason told him "to stick it".
But eventually, Jackie looked her husband's killer in the eye.
"I thought 'this is going to be my only opportunity to get some answers'," she says.
"He was very nervous ... hyperventilating. Shaking. Sweating," she says.
"I looked at the person he was now, years later. He was not some thought kid any more."
He was looking for forgiveness, but he didn't get it.
"I think so, that's his problem. Not mine," she says.
HEARNE FREED
Hearne was released from jail in March, 2014 after 16 years behind bars.
He married his prison psychologist after a prison affair, has a child, and is still on parole.
He won't answer Murder Uncovered's questions about some of his Facebook friends with criminal histories.
He's not the only one staying silent.
Peter Forsyth's son, Mitchell is now 22.
Asked what he'd say to his father's killer if he got the chance, Mitchell's voice drips with contempt.
"What would I say to him? Nothing. I wouldn't give him a second of my life."