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The 5,000-page report was 12 years in the making and the costliest in British history at close to 200 million pounds. Chaired by Lord Saville, a British judge, the inquiry took evidence from 2,500 people from 1998 to 2004.
Victims' families hope the report will say their loved ones were innocent and lay the blame on the soldiers, while critics fear that re-opening the wounds of 38 years ago could cause trouble for Northern Ireland's fitful peace process.
"Only one thing is certain: it is impossible for Lord Saville to achieve total satisfaction," said Paul Bew, professor of Irish politics at Queen's University in Belfast and adviser to the inquiry from 1998 to 2001, in a Daily Telegraph column.
The events of January 30, 1972, became known as Bloody Sunday after soldiers opened fire during an unauthorised civil rights march in the town of Londonderry, in an area that was deeply hostile to British rule over Northern Ireland.
The troops shot dead 13 protesters on the spot and wounded another 14, one of whom died weeks later. The soldiers said they shot at people who were armed with guns or nail bombs, which was strongly denied by witnesses and by relatives of the victims.
Bloody Sunday drove hundreds of new volunteers into the clandestine Irish Republican Army (IRA), which stepped up its brutal campaign for Northern Ireland to secede from the United Kingdom and become part of the Republic of Ireland.
With close to 500 killings, 1972 became the bloodiest year in the Northern Ireland conflict, which pitted the IRA against the British authorities and against unionist armed groups fighting for the province to stay under London's rule.
British media have speculated that the Saville report could lead to attempts to prosecute the Bloody Sunday soldiers. That would be sure to infuriate the unionist camp.
"I think many people would be appalled if soldiers were pursued but other people who were law breakers every day were not," said Gregory Campbell, a member of parliament from the Democratic Unionists, representing the East Londonderry area.
He specifically mentioned Martin McGuinness, who was the number two figure in the IRA in the city at the time of Bloody Sunday and is now the deputy first minister of Northern Ireland in a power-sharing government of republicans and unionists.
Other critics say it would be divisive to go after the Bloody Sunday soldiers when many killers from both sides of the Northern Ireland conflict were freed from prison early as part of the peace process launched by the 1998 Good Friday agreement.
The Saville inquiry was promised by former Prime Minister Tony Blair at a time when he was trying to secure republican support for what would become the Good Friday agreement.