The Bloody Sunday Inquiry has finally ended after seven years and at a cost of about £150m.
Soldiers shot 13 people dead in Derry on Bloody Sunday
After hearing from more than 900 witnesses, Lord Saville and his two colleagues have retired to write their final report.
The inquiry has been investigating the deaths of 14 civilians shot by soldiers during a civil rights march in Londonderry in January 1972.
Counsel to the inquiry Christopher Clarke QC said he hoped it had played a part in enabling people to come to terms with the events of the day.
He said he hoped it had held to account people "whose actions or inactions contributed to what happened".
Bloody Sunday inquiry facts
Lord Saville held his first hearing at Derry's Guildhall in April 1998.
The inquiry began to hold public hearings in March 2000
The tribunal has now sat for 433 days.
It has heard evidence from 921 witnesses.
There have been 1,555 written statements from witnesses.
The final bill will be around £150m.
The final report is expected next summer.
In a closing speech on Tuesday, Mr Clarke also paid tribute to the families of the victims who, he said, "deserved credit" for bringing about the inquiry and for enduring anxiety, tension and frustration during proceedings.
Earlier, he told the tribunal judges that they must decide if one of the victims had nail bombs when he was shot.
Gerald Donaghy was photographed at an Army post with four nail bombs in his pockets but a number of civilians, who tried to take him to hospital, told the tribunal that he was not armed.
Mr Clarke said it was difficult to believe that Mr Donaghy had the nail bombs and that they were not noticed by those who tried to help him.
He added that it was also difficult to believe that they were planted by the police or the Army.
Mr Clarke said it was up to the judges to say what probably happened.
Lord Saville's report is not expected until 2005
In the first part of his closing speech on Monday, Mr Clarke said the central question was why and how civilians were killed or wounded on Bloody Sunday.
He said it was still unclear which soldiers shot the 27 civilians on the day.
His speech was a brief summary of eight to 10 volumes of written material collated after more than four years of evidence-gathering.
It was intended to constitute an overview of the issues for the tribunal to decide and an indication of a range of conclusions the tribunal might reach.
The Bloody Sunday inquiry was established in 1998 by Prime Minister Tony Blair after a campaign by families of those killed and injured.
Lord Saville of Newdigate and the Commonwealth judges accompanying him on the inquiry began hearing evidence in March 2000.
The inquiry has heard evidence from leading politicians, including the prime minister at the time, Sir Edward Heath, civilians, policemen, soldiers and IRA members.
Lord Saville's final report and conclusions are not expected to be made public until next summer.