Sunday 30 January 1972 is remembered as among the most fatal – and momentous – dates in thirty years of violence in the region.
Within the community where it happened – the legacy of Bloody Sunday are painted on the structures and etched in public consciousness.
A civil rights march was held on a cold but bright afternoon in the city.
The demonstration was challenging the practice of imprisonment without charges – imprisoning people without legal proceedings – which had been established following three years of conflict.
Troops from the Parachute Regiment killed multiple civilians in the neighborhood – which was, and still is, a strongly Irish nationalist community.
A particular photograph became especially iconic.
Images showed a religious figure, Fr Edward Daly, using a stained with blood cloth in his effort to shield a crowd transporting a youth, the fatally wounded individual, who had been mortally injured.
Media personnel recorded much footage on the day.
Historical records includes Father Daly telling a journalist that troops "just seemed to shoot indiscriminately" and he was "totally convinced" that there was no justification for the shooting.
This account of the incident was disputed by the initial investigation.
The Widgery Tribunal concluded the military had been attacked first.
Throughout the peace process, Tony Blair's government commissioned a new investigation, in response to advocacy by bereaved relatives, who said the first investigation had been a cover-up.
During 2010, the report by the inquiry said that overall, the paratroopers had initiated shooting and that none of the victims had presented danger.
The contemporary head of state, the leader, expressed regret in the House of Commons – stating killings were "unjustified and unjustifiable."
Authorities began to examine the incident.
A military veteran, known as Soldier F, was prosecuted for killing.
He was charged over the deaths of James Wray, 22, and twenty-six-year-old another victim.
Soldier F was further implicated of seeking to harm multiple individuals, Joseph Friel, more people, another person, and an unidentified individual.
Exists a judicial decision preserving the veteran's identity protection, which his lawyers have maintained is required because he is at danger.
He told the investigation that he had exclusively discharged his weapon at people who were possessing firearms.
The statement was dismissed in the concluding document.
Material from the investigation could not be used immediately as testimony in the court case.
During the trial, the defendant was shielded from sight using a blue curtain.
He spoke for the opening instance in the proceedings at a session in that month, to reply "not responsible" when the allegations were put to him.
Kin of those who were killed on that day travelled from Londonderry to the judicial building daily of the trial.
A family member, whose relative was fatally wounded, said they were aware that listening to the case would be difficult.
"I visualize all details in my mind's eye," the relative said, as we examined the key areas referenced in the trial – from the street, where his brother was killed, to the adjacent the courtyard, where James Wray and William McKinney were fatally wounded.
"It even takes me back to my location that day.
"I participated in moving my brother and put him in the medical transport.
"I relived the entire event during the testimony.
"Notwithstanding experiencing all that – it's still valuable for me."
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