Derry's Bloody Sunday families have accused Democratic Unionist MP Gregory Campbell of using the Saville Inquiry as a "political football".
The families spoke out after Mr Campbell described the tribunal as a "staggering waste of public expenditure".
In response to a parliamentary question, the East Derry MP was told that the inquiry – now in its sixth year – had cost £90 million to date.
Established by Prime Minister Tony Blair in January 1998, the inquiry started hearing oral evidence in March 2000. So far it has sat on 360 days to hear the evidence of eyewitnesses, politicians, former soldiers, and expert witnesses. Mr Campbell has been told that the largest portion of costs to date, more than £38 million, has gone to lawyers.
He was also told that £12 million had been spent on IT. The inquiry has invested a huge amount on state-of-the-art IT systems in Derry. It was forced to duplicate the system in London when former soldiers refused to travel to Derry to give evidence.
Mr Campbell said: "The issue of legal fees does not surprise me even though it is appalling.
"But it is the issue of the salaries and IT bill; £12 million is a staggering amount to be spent on an inquiry the result of which will satisfy no-one."
His comments were rejected by John Kelly whose teenage brother, Michael was one of those shot dead.
Mr Kelly accused the MP of using the inquiry as a political football. He said Mr Campbell should spend more time examining the evidence before the Inquiry than criticising the quest for justice.
Mr Kelly called on Mr Campbell to recognise that the Saville Inquiry was about the basic human right to life and about the value placed on human life and should never been seen as a political issue.
The Saville Inquiry is currently in summer recess.
