Sergeant Steven Roberts was one of the first British soldiers to be killed in the Iraq war. Since his death his widow Samantha Roberts has campaigned to find out how he died.
Mrs Roberts has been critical of the MoD over the death of her husband
Now three years on an army report has confirmed he died because he was not wearing enhanced body combat armour.
Sergeant Roberts, from Shipley, West Yorkshire, was accidentally shot dead by one of his own men when UK troops opened fire during a riot near Basra, just three days into the war.
An Iraqi civilian Zaher Zaher was shot and killed in the same incident.
Sgt Roberts' widow Samantha was left with the knowledge that her husband's life could have been saved had he been wearing bullet-proof plates on his body armour.
Shortly after his death, Mrs Roberts recalled how her husband had been concerned about handing over his special body armour before going into battle saying he was "nervous" at having to do so.
She said at the time: "He was given an order, he agreed with that order to give it to infantrymen who were more at risk than him."
On the day of her husband's funeral Mrs Roberts' father-in-law gave her a recording of an audio diary kept by Sgt Roberts.
In the tapes her husband voiced his concerns over lack of equipment describing the situation as a "joke".
"Things we have been told we are going to get, we're not, " he was heard saying.
"It's disheartening because we know we are going to war without the correct equipment.
"It will be interesting to see what armour I actually get. I will keep you posted," he said.
Mrs Roberts also said her husband had felt it necessary to spend nearly £1,000 of his own money on his kit.
An initial Ministry of Defence report in 2003 said the 33-year-old tank commander, from the Second Royal Tank Regiment, had been ordered to give his protective body armour to another soldier and that had he had the right body armour his life may have been saved.
In her quest for answers Mrs Roberts met the then Defence Secretary Geoff Hoon in January 2004, and following the meeting later called on him to resign over her husband's death.
On the day Sgt Roberts died he was manning a checkpoint which was stopping and searching vehicles for weapons at Az Zubayr near Basra.
A Crown Prosecution Service report into his death said Zaher Zaher had approached him and started throwing stones.
Sgt Roberts, who was standing alone outside his tank, pointed his pistol at Mr Zaher after he failed to stop when the British soldier held up his hand.
Sgt Roberts pointed his pistol at Mr Zaher but it malfunctioned allowing Mr Zaher to come further forward.
Warning shots from another soldier did not deter Mr Zaher prompting soldiers from two tanks to fire "warning shots" at Mr Zaher.
Mr Zaher was fired upon again after the soldiers felt he still posed a threat.
Both Sgt Roberts and Mr Zaher were declared dead at the scene.
Earlier this year the Attorney General Lord Goldsmith said there was insufficient evidence to prosecute British troops over the deaths of Sgt Roberts and Mr Zaher.
Lord Goldsmith told the House of Lords: "Although Mr Zaher was hit and severely injured in the arm, two of the bullets struck Sergeant Roberts in the torso and he fell to the floor fatally wounded."
But following this report Mrs Roberts said that while she accepted the decision not to prosecute was "based on their careful scrutiny of the evidence" she still felt she knew "little more about how he came to meet his death than I did when I was first told that he was killed."
Now the latest Army Board of Inquiry report says: "Had Sgt Roberts been wearing correctly fitting and fitted ECBA (enhanced combat body armour) when this incident unfolded, he would not have been fatally injured by the rounds that struck him."
And it criticised the Ministry of Defence for failing to give "timely attention at the appropriate level" to shortages in the life-saving kit.
The report also found the L94 machine gun which fired the shot which killed Sgt Roberts was known to be inaccurate at short range. The gunner who fired it had not been taught about problems with it during his training.
The inquiry criticised "inadequate" procedures and recommended all gunners should in future be educated on the gun's shortcomings.
The army has responded to the report saying it is working "quickly" to learn lessons from this.
Sgt Roberts' widow has yet to comment on its findings but is expected to make a statement later this week.