How does a killer escape justice for decades? Why does the death of a schoolgirl go unsolved even when police believe they know who did it?
These are some of the questions we're exploring in a new podcast from the Eastern Daily Press called Unfinished. In it, we take a fresh look at East Anglia's most troubling cold cases.
The first three episodes examine the disappearance and death of 14-year-old Watton schoolgirl Johanna Young at Christmas 1992.
You can listen to episode one below, or on iTunes, or by searching for Unfinished on your usual podcast provider.
•The night she went missing
At 7.30pm on December 23 1992 Johanna Young left her family home on Merton Road in Watton for the last time.
Three days later, her body was found floating face down in a freezing water-filled pit near woodland about a mile from her home.
The night Johanna went missing was foggy with temperatures dropping to minus three degrees.
The Watton High pupil was wearing a purple anorak over a bottle green bodysuit, blue jeans and black trainers as she walked from her house to the High Street through the housing estate where she lived with her parents, sister and brother.
Friends saw her on the High Street near a supermarket called the Gateway where the town's teenagers used to hang out.
One witness said she seemed down but her family said she was happy. She was last seen alive at around 8.30pm on the High Street.
Johanna's parents, Rob and Carol, thought she must have stayed with her boyfriend, Ryan, that night due to the bad weather.
What they didn't know was they had split up a couple of days earlier and she had taken down all the Christmas cards in her room.
They first time they realised their daughter hadn't come home was when her alarm clock rang at 6am on Christmas Eve.
Johanna was meant to be getting up for her paper round.
When she had not shown up by 7am they called the police.
A search across the town began. Police quizzed 30 friends and relatives, visited pubs and clubs. They searched farm buildings and woodlands.
The family abandoned their Christmas Day plans to appeal through the media for her to come home
Then on Boxing Day afternoon there was a breakthrough.
A dog walker found Johanna's black trainers tucked neatly in the undergrowth on a little used track, east of the town centre, called Griston Road.
Her underwear was then found around 200 yards further down road away from trainers.
Police search teams found her body later that evening nearby at 8.20pm.
She was floating face down in an icy pond at the edge of a woodland called Wayland Wood.
Her body was found around 130 yards from her shoes near a path called Gilman's Drift, known to the locals as Muddy Lane, which leads on to Griston Road.
Her jeans had been removed and were missing. Her body was covered in scratches.
She had a fractured skull but died from drowning. She had been dragged unconscious to the pond from a nearby path, probably by two people.
•After the body was found
On December 28 1992, two days after her body was found, Johanna's parents held an emotional press conference.
'You hear so much of this sort of think happening,' her dad said. 'Make sure you know where they (your children) are going because I wish to hell I had done that,' her mum Carol sobbed.
On the streets of Watton there was fear.
Police initially thought Johanna had been sexually assaulted and people in the town believed a sex attacker was on the loose.
Adding to that fear was the death of another teenage girl a few weeks earlier in Norwich which is still unsolved today.
Natalie Pearman, 16, had been working as a prostitute in the city's red light district. She was found strangled to death at Ringland Hills in a lay-by on the outskirts of Norwich on November 20 1992.
The Johanna Young case was given to an experienced officer, Detective Superintendent Mike Cole. He had solved plenty of murder cases before this one and was confident of getting a similar result.
Det Supt Cole told ITV Anglia at the time he was looking for a 'calm, brutal killer'.
Officers put posters up around the town, a thousand questionnaires were distributed to homes, 4,500 lines of enquiry were pursued, while police took 1600 statements.
But all to no avail. Detectives ran into problems with the investigation early on.
The first problem was a lack of any witnesses about the night Johanna went missing. It was a cold, foggy evening just before Christmas.
There was also a tension between police and people in Watton about how police went about their investigation, something we explore in more detail in the podcast.
Police were convinced the killer was a local, young man and therefore someone in Watton was hiding the killer from them.
But they struggled initially to get evidence from the youth scene which Johanna was part of. This again is explored in detail in Unfinished.
Ultimately, officers become frustrated about the lack of information they got, while the townsfolk became frustrated about the lack of progress in the investigation.
Exemplifying the problems police faced was a mysterious postcard.
•The postcard
On New Year's Eve 1992 - a week after Johanna went missing - a postcard dropped through the door of the Eastern Daily Press office on Rouen Road in Norwich.
It said: 'Griston Rd. Watton 23/12 9pm' 'm/cycle, youth and girl'. It contained a stick drawing of a motorbike, a boy and a girl, suggesting that around 90 minutes after she left her house Johanna was with a boy on a motorcycle on Griston Road.
The person who drew it disguised their handwriting, according to a handwriting expert this newspaper asked at the time.
They used both their right and left hands to draw it. They also sent the card from a Norwich post box - not a local Watton one.
The card has been with Norfolk Police ever since. It could be a key bit of evidence, or it could be a prank.
•A motorbike?
The theory that Johanna met a man on a motorbike that night, which is supported by the postcard, has never been ruled out.
Detective Chief Inspector Marie James, from Norfolk police's cold case team, said last year: 'It was always a possibility, though never proven, that [the head injury] could have been caused by coming off a motorcycle.'
There are no other injuries on her body to suggest a motorbike accident but the inquest into Johanna's death did establish that she had a very thin skull, meaning she could have been knocked unconscious by a fall.
A witness in 1993 also described seeing a couple leaning on a motorbike that night. The couple has never been identified.
That witness, a dog walker, reported seeing a young woman, who fitted Johanna's description, and a young man standing at the entrance of Gilman's Drift/Muddy Lane.
It has led to theory that she fell off the back of a motorbike and hit her head. The driver then panicked, thought she was dead, removed her lower clothing to make it look like a sexual assault and dragged her to the water.
But against this theory is a lack of motorbike tracks on the road from that night - and no hard evidence that a motorcycle was seen or heard being driven on Muddy Lane that night.
A key witness who helped police narrow done the time of death also did not see or hear a motorbike. He was walking his dog down Muddy Lane just after 11pm on December 23. His dog heard someone running in the darkness.
His dog barked and a figure stumbled into a water trough. He shouted at the person but they disappeared.
The man ran to fetch a torch but by the time he had returned, all was quiet and he had no idea who it was he had heard.
•Johanna's jeans
When Johanna's body was discovered, police found her shoes and underwear - but not her jeans.
Then on January 19 1993, four weeks later, her jeans appear close to where her body and clothes were found. They had been washed and there was no DNA on them.
Where were they between her death and four weeks later when strewn on a bush by Griston Road?
Why did the killer take the jeans but not her shoes or underwear?
Those questions have puzzled police for 26 years.
Retired Norfolk police officer, Chris Clark, who now investigates cold cases, told our podcast that the killer likely believed his DNA was on the jeans which is why he took them and not other clothing.
There are also no signs of a struggle which means, he suggests, that her shoes, jeans and underwear were removed after she had been knocked unconscious.
•'Youthful prank'
Much of the evidence in this case, as we discover, suggests that nobody set out to kill Johanna that night.
The pathologist told her inquest in June 1993 that her skull was likely fractured by a fall rather than a blow to the back of the head. She had a very thin skull and could have been knocked unconscious when she fell on to the icy ground.
The theory goes that the killer then mistakenly believed Johanna was dead and returned later that night with someone else to move the body.
They then drag Johanna to the pit. Police discovered drag marks on the lane by the pit and they fitted with scratches on the lower half of Johanna's body. That meant she was dragged in a U-shape with one person holding her top half and the other her feet – meaning two people were involved.
'What may have started as a youthful prank finished up in tragedy,' said coroner Christopher Starking at the inquest.
•A local killer?
For 26 years police have maintained that the killer is local.
'It is very likely she went down there with somebody of her own age,' said Det Supt Mike Cole at the time.
Det Ch Insp Marie James said last year the key to solving the case still lay in the local community.
There are several reasons for this. Johanna appears to go down Muddy Lane/Gilman's Drift of her own accord, suggesting she knew the killer.
The killer returned to the scene to cover up her body at least once and to return the jeans.
Perhaps most importantly, no stranger to the area would have known about the existence of that pond and no stranger, even if lost, would be going down a muddy track at night in Watton on December 23.
That means she probably met someone she knew, someone local, and the person who helped move the body is also local.
Four men were arrested and released without charge at time.
But the person who helped move the body has never been identified.
•Where was she going?
Johanna was last seen alive on Watton High Street.
One theory about what she was doing in town earlier that night was going to see her boyfriend Ryan, 17.
He was initially a suspect and was questioned by police but was quickly ruled out. He was out that night visiting a friend.
To get to Muddy Lane she would have to walk down the Norwich Road. Ryan lived off that road, on a turning on the right after Muddy Lane, but would not have been in if Johanna had called that night.
'I reckon she might have been coming to see me,' Ryan later said. 'She wouldn't have been going down there if we hadn't split up,' he told ITV Anglia in 1993.
Ultimately police still don't know where she went between last being spotted on the High Street.
•The suspect
'The person who did this will make a mistake, may be not this week but be it next week, month or even year, he will and when he does we will get him,' Norfolk police's spokesman PC Peter Walmsley told the press on June 9 1993.
The police's main suspect in this case lived near Johanna and was aged 20 at the time.
He was arrested in February 1993 and held for three days but was released without charge. Nothing has been proven against him.
In November 1993 he was in court for a driving offence which his solicitor blamed on the pressure of being suspected as Johanna's killer.
'He has been treated and convicted by Watton,' the solicitor said.
Around town today the people we speak to for the podcast still believe police had their man – but could not get the evidence.
PC Walmsley told us he remembered the suspect having deep scratches on his hands and arms. That is relevant as the pit Johanna's body was found in was covered in brambles.
The suspect had also been in trouble with the law before, but a lot of the evidence against him in this case was circumstantial.
He also had an alibi - he said he was at home with his mum the night of December 23 and she backed him up.
The only time he has been quoted about this case was in an article by journalist Nick Davies in 1993. Here is what he said:
'Everybody knows they took me in. My solicitor says I should sue them. My car wasn't even on the road that night. The clutch had gone and it wouldn't even go round the block. Them people who said I had scratches was wrong. I never had scratches. They kept on at me, they took intimate body samples, they done my car. I kept telling them I was at home all evening. My mum was there. But she don't remember things very well. I hardly even knew Johanna, just to say Hallo to. I didn't know her well.'
•2014 arrests
At Christmas 2013, Norfolk police and Johanna's parents renewed their appeal for information.
It led to the best response the Constabulary has ever had to a cold case.
Among the calls was a tip-off which led to two arrests.
In April 2014 a man in his 40s from the Watton area was arrested. A second man in his 30s from the Thetford area was also arrested. The two men knew each other and lived in Watton at the time of Johanna's death.
But by the summer of 2014 both had been released, with no further action taken against them.
Then in May 2014 a local businessman came forward. For 21 years he had only told his wife about a hooded man he stopped and gave a lift to just half a mile from where Johanna was found, on the night she went missing.
The man he gave a lift to was in his late teens, scruffy and acting suspiciously as he drove him along Norwich Road to Scoulton, which is about five miles away.
He was not either of the two men arrested by police and as far as we know has never been identified.
Then in December 2017, after a 25th anniversary appeal two more new leads came forward. Again they ultimately came to nothing but the case remains one of nine cold cases on Norfolk police's website which they still hope to solve.
•Why we're looking at it now
This Christmas marks 26 years since Johanna left her home, never to return.
Annual appeals have regularly run in the Eastern Daily Press and have brought new leads to light. This time we wanted to tell the story of what happened to Johanna through a podcast, in a different way, in the hope it may reach more people and lead to more information.
We wanted to make a lasting record of people's memories of that time and, on the way, uncover information about why this case has remained unsolved for 26 years.
The Unfinished podcast contains information never heard publicly before. You can listen to it here on iTunes.
•The first three episodes of Unfinished will be released on Friday October 26, Friday November 2 and Friday November 9.
•A later article will explore some of the podcast's fresh findings about why this case remains unsolved 26 years later.
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