Could Mitchell be innocent of Jodi murder?
Several hundred yards away at the Newbattle entrance to Roman's Dyke path - the muddy lane linking Jodi's Easthouses council estate with Newbattle on the other side - is another ornamental sunflower.
It is there as a constant reminder of the bright young life ended on a summer evening in 2003, when 14-year-old Jodi was horrifically slashed and stabbed, her clothes ripped off and her body left in the weeds and undergrowth behind a wall next to the quiet country path.
Almost four years on and today the boyfriend convicted of her killing, Luke Mitchell, passes another day of his 20-year sentence in his high-protection cell at Polmont Young Offenders Institution. Of course, if Jodi so brutally died at his hands, then that is exactly where he should be.
But could the unthinkable be possible? Could there be a real possibility that he shouldn't be there at all?
Soon his defence team, led by one of the country's sharpest legal minds, Donald Findlay QC, will take that notion a stage further - to the Court of Appeal, where they will argue that the High Court trial that led to Mitchell's sensational conviction was shockingly flawed.
Central to their argument is that Mitchell was denied a fair trial because it was held in Edinburgh before a local jury which may have been prejudiced by the surge of publicity. They will argue that key elements of evidence were not shared by the prosecution and that police methods used to identify Mitchell were unfair.
Alongside that, it is looking increasingly likely that they will attempt to secure his freedom by focussing on so far unidentified DNA evidence found on Jodi's body and the introduction of possible new evidence which is claimed to link Jodi's death to a drug addict who it is said fantasised and wrote about killing women.
Soon the case will be featured in a new book analysing alleged miscarriages of justice, and on television later this week - when Mitchell's mother Corinne will defend her son.
Her home in Newbattle Abbey Crescent is just a short stroll from where the sunflower memorial guards the entrance to Roman's Dyke.
At the Mitchells, however, signs are plastered over the front door, warning away unwelcome visitors.
Corinne Mitchell refuses to discuss her son's case until after theprogramme on Wednesday evening. However, a close family friend insists: "She is totally convinced that Luke is coming home and that the appeal will be successful. She has never doubted he is innocent.
"But she is worried about how things will go when he does come out because she knows there are people out there who will want to get him. She just tries to shrug it off and says it will be like a new chapter in a new nightmare.
"Corinne thinks people haven't been able to see the real side of Luke. She tells people that he's a gentle boy who wouldn't have hurt a hair on Jodi's head."
The verdict, the friend adds, stunned her. "She can't believe Luke is still locked up. She thought he'd be out within a few weeks.
"One thing she deeply regrets, though, is that television interview they gave on the day of Jodi's funeral. Corinne says Luke wanted to go to pay his respects but they were conned by the TV people and it ended up looking really bad."
The friend says that claims she fabricated an alibi for her son were down to misunderstandings.
"Corinne was being asked to remember what she was doing at a specific time on an otherwise uneventful day. How can anyone remember exactly what time they did something they do every day?
The friend adds: "Among it all, though, she has been really touched by the support she's received from so many people - not everyone out there believes that Luke was treated fairly and deserved to go to jail."
Certainly author Sandra Lean, with a university background in psychology and sociology and who has spent months researching the case, doesn't believe Mitchell, now 18, should be behind bars. In fact, having pored over evidence and quizzed key people, she is prepared to go much further: "I believe he is innocent," she declares
"I started looking into this case with the hope of finding proof to uphold the guilty verdict. But the more I looked at it, the less that looked likely. And I found more evidence pointing to other people than I did to Luke Mitchell."
There are, she says, several areas of doubt - none more so than the nature of the case, which was driven in the early stages by the new collusion between police and prosecutors, where investigators and Crown agents work closely to secure a guilty verdict.
"I think it was a case of 'here's the story we're going to tell'," claims Lean, whose book No Smoke: The Shocking Truth About British Justice was inspired by the Mitchell case and forms the basis of Wednesday's television investigation. "And the case was made to fit around that.
"But there is reasonable doubt in this case, there's no DNA or forensic evidence, the suspect was not identified at or near the scene and there was an over-reliance on expert witnesses," she adds. "There was also crucial evidence given by others with a vested interest in the outcome, there are questions about the timescale and the suspect's physical ability to commit the crime."
Psychology student and education worker Colin Bowman felt so uncomfortable with the case that he launched an internet forum aimed at thrashing out its details within weeks of the verdict. The site has had thousands of hits including many from people clearly directly involved in the case with intimate knowledge of Mitchell, Jodi and the investigation.
"The problem is, Luke may be guilty, but the hard evidence isn't there," warns Bowman.
He agrees with Lean that a string of troubling elements could well raise doubts over Mitchell's conviction: from the lack of forensic evidence to the narrow time frame in which a 14-year-old boy would have had to commit a gruesome killing, return home, change his clothes and re-emerge.
"One of the big problems is the lack of forensic evidence," he stresses. "It looks like the police allowed the crime scene forensic evidence to be washed out, that the scene was left unprotected for several hours in the rain overnight. There must have been forensic evidence and to lose that would be catastrophic."
The portrayal of Mitchell as an oddball fascinated with the music and artwork of goth rocker Marilyn Manson, who kept bottles of urine in his bedroom, played with knives and penned school essays praising Satan and expressing desires to kill, all helped create a public image of a deeply troubled young man, Bowman points out.
"But," he argues, "they do not prove his guilt." The case may have been circumstantial, but police in charge of the investigation have steadfastly insisted they got their man. The officer in charge of the investigation, now retired Chief Superintendent Craig Dobbie, spoke after the trial of how he believed Mitchell turned on Jodi when she became upset after discovering he was two-timing her, mutilating her body to emulate the infamous murder of actress Elizabeth Short, known as the Black Dahlia - captured in paintings by Marilyn Manson.
That, against a background of a troubled youth set the scene for the case that followed.
But justice campaigner John McManus, of Mojo Scotland, warns that cases based on circumstantial evidence - such as Mitchell's - represent a worrying trend for Scottish justice.
"What worries me in recent years is how circumstantial evidence is now able to sway a jury.
"Our judicial system is meant to be based on the fact that everyone is innocent until proven guilty.
"It's down to the prosecution to show that the burden of proof and weight of evidence shows guilt," he adds.
Should Mitchell leave his cell in Polmont a free man - at least until any retrial - it's unlikely that Dalkeith's tight community will feel any need to celebrate.
"If he did it and he gets out on a technicality, then he'd be in trouble," says one passer-by in the town's main street. "Too many people would want to go for him, he wouldn't be able to stay here."
Bus company worker Ian Clarke, 47, agrees: "There are strong feelings about what happened - people are going to react.
"Then again, if it comes out that he didn't do it, well, you've got to wonder who did."
No Smoke: The Shocking Truth About British Justice by Sandra Lean (Diggory Press) will be published in mid-April and available via webseller Amazon
Brutal attack that led to a 20-year sentence
JUNE 30, 2003: Schoolgirl Jodi Jones arrives home from St David's RC High School at 4.05pm
4.55pm: Jodi leaves her home at Parkhead Place, Easthouses, apparently to meet her boyfriend, Luke Mitchell. He lives in Newbattle, around a mile and a half away.
5pm: She arrives at the entrance to the dirt path behind Newbattle Community High School.
5pm-5.45pm: Forensic experts say Jodi died sometime between 5pm and 5.45pm. She is brutally attacked, her throat is cut and she is repeatedly stabbed. She suffers 320 injuries of varying types and severity. Mitchell claims he was either at home or elsewhere at the time.
5.40pm: Mitchell phones Jodi's home to ask where she is. Ten minutes later he calls a friend and arranges to meet up in woods at Newbattle Abbey College.
10pm: The alarm is raised when Mitchell replies to a message from Jodi's mother that he hasn't seen her.
11pm: Jodi is reported missing to the police. Mitchell takes his trained tracker dog and joins Jodi's sister Janine, her grandmother, Alice Walker, and Janine's fianc, Steven Kelly to search for her.
11.50pm: Her body is discovered by Mitchell.
JULY 1, 2003: Jodi's body is left uncovered and exposed to the elements for eight hours after it was first discovered, possibly risking the destruction of vital DNA evidence.
SEPTEMBER 3, 2003: Mitchell asked not to attend Jodi's funeral. He gives an interview to a television channel, posing with his mother at the graveside and protesting his innocence. The interview is later analysed by Crown "expert", San Francisco psychologist Dr Paul Ekman, who concludes his facial "micro expressions" reveal him to be lying.
NOVEMBER 23, 2003: Police submit a report to the procurator fiscal, naming Jodi's boyfriend as sole suspect.
NOVEMBER 18, 2004: Mitchell denies assaulting Jodi by striking her on the head and body, compressing her neck, striking her on the head, mouth and body with a knife and murdering her. He also denies unlawful possession of knife or knives before the incident, and being involved in supplying cannabis.
JANUARY 21, 2005: The members of the jury take just over six hours to declare Mitchell guilty of murder by majority verdict. He is later sentenced to serve a minimum of 20 years.