OUTSIDE: A kango drill and space by Mr Balkwell's body and found outside the mixer
IT is the question that no one has been able to satisfactorily answer so far.
If Lee Balkwell died in an accident while drilling out dried cement from inside the drum of a cement mixer with his boss, why were the Kango drills, spades and light they were supposedly using not still inside the drum when the emergency services arrived?
Mr Balkwell, 33, was found dead by paramedics just after 1am wedged between the drum and chassis of the vehicle parked in an isolated industrial area used by a concrete business in South Ockendon, Essex.
Essex Police botched the initial investigation and treated it as an industrial accident, paying Mr Balkwell's family a four figure sum in 2015 after they sued the force.
Now a team of former Met Police murder detectives have said in a report that Mr Balkwell is likely to have been murdered and the scene staged to look like an accident.
This report was prepared ahead of an application to the High Court for a judicial review that Lee's father, Les Balkwell, 71, hopes could force Essex Police to reinvestigate the mysterious 2002 death.
KILLED: Lee Balkwell was 33 when he died
The application is being prepared after Essex Police said it was formerly closing the case once and for all.
Mr Balkwell's employer Simon Bromley, 48, was cleared at Chelmsford Crown Court of gross negligence manslaughter, more than 12 years after the July 2002 death, but convicted of failing to ensure his health and safety.
Mr Balkwell senior remains convinced foul play was involved, but a series of further reviews of the case after the prosecution concluded there was no new evidence.
Human rights lawyer Kirsty Brimelow QC is preparing a High Court judicial review application which will ask judges to force Essex Police to get a completely independent police force to carry out a full reinvestigation of the death.
The judicial review application is expected to raise evidence from private investigators TM Eye, who have investigated the case for four years, and claim to have found injuries on Lee's hands and head visible in post mortem photographs that they believe could not have been caused by the accident described.
The team consists of five former Met Police murder detectives, including Stephen Hobbs, a former detective superintendent from the Met homicide command and Northern Ireland historical enquiries team who has worked on more than 200 murder cases.
TM Eye believes it has uncovered a motive for Lee's death.
ACCIDENT: Simon Bromley insists his account of the accident is true
Simon Bromley has always insisted that there was no criminal act in Lee's death.
He has always insisted the two were drilling hardening cement from inside the mixer drum, at an industrial area next to the Bromley's home Baldwins Farm, each using a Kango drill, connected by an electrical cable, and a spade.
Mr Balkwell left the farm at 11.37pm to eat a Chinese takeaway, but returned just before midnight.
Police accepted Mr Bromley's account that they resumed drilling out cement in pitch black for another hour.
Mr Bromley said they had to drill into an area of hard cement, then one would get out and move the drum round a few inches to get to another patch while the other remained inside.
He claims that while doing this, at just before 1am, Mr Balkwell must have tried to climb out of a tiny inspection hatch at the exact moment that the vehicle malfunctioned and the drum went spinning round, crushing Mr Balkwell.
After jumping out and being unable to get Lee out, he said he called 999 from his parent's A property.
A Kango drill stuck in a pile of cement next to Lee's body outside the mixer drum
TM Eye says his account cannot be true because of the positioning of the drills, spades and lighting outside the vehicle when emergency services arrived.
David McKelvey, TM Eye managing director, said: "If we believe his account then the drills, spades, and lighting would have been tangled up inside the drum.
"But they were outside in piles of cement as if work had finsihed so the scene must be staged. This has never been explained."
TM Eye's report also says the mixer's tachograph record shows no movements from 9.10pm until 12.57am, then 1.03am, when Lee died, meaning no drilling out as described was taking place, in its view.
The report added: "It is also incredible that Essex/Kent Police are still prepared to accept the version of events that Lee died in a tragic industrial accident.
"Any open minded person reviewing the evidence would come to the conclusion that his death was suspicious and should have been treated as a murder from day one.
"At no stage has Essex or any other police service carried out a thorough independent open, honest and transparent homicide investigation."
In 2012 the then Independent Police Complaints Commission ordered a reinvestigation by a separate police force after rapping Essex Police over its failings.
However, the force instead got Kent Police, which it shares a serious crime squad with, to review earlier inquiries.
DETERMINED: Les Balkwell has battled for 16 years for 'the truth' about his son's death
Essex Police were sent a series of questions specifically asking how the equipment could have been found outside the vehicle and why the tachograph showed no movements between 9.10am and 12.57am, but it refused to comment saying there was pending legal action.
We also wrote to Simon Bromley, who has stuck to his account from the outset, care of Baldwin's Farm, asking similar questions, but there has been no response.
Early investigators never pinned down Mr Bromley about this anomaly, but in a statement he made ahead of the inquest, he said he could not remember how the equipment ended up where it was.
Mr Bromley junior has never given an interview about the death.
In 2012, after Mr Balkwell held a press conference making claims of foul play in connection with his son's death, Mr Bromley's dad, Simon Bromley, 71, said he was sick of insinuations his son might have murdered Lee.
The press conference was held after it emerged in a 2012 Independent Police Complaints Commission report over Lee's death that police launched a covert operation into Simon Bromley’s actions in 2005.
It began after police received intelligence of a possible motive for Simon Bromley killing Lee.
Simon Bromley was at no point arrested or charged over the death in connection with the covert inquiry, and in July 2005 police ruled out the intelligence as inaccurate.
Mr Bromley senior said: “We were never asked about a motive, because there is no motive. This was a terrible, tragic accident.”
He added: “Lee was like one of the family. He was a great loss. Simon felt terribly guilty. It made him ill. He would cry his eyes out about it. He said he wished it had been him and not Lee who died.”