Patrick Mercer MP has told Daybreak that the conclusions from the al-Sweady inquiry will "not be satisfactory."
He said the families "need to know the truth", but explained that both sides of the argument were "completely polarised".
Today an inquiry into the deaths of 20 or more Iraqis will begin, expected to last until 2014.
It is alleged that UK soldiers killed unarmed civilians and tortured detainees.
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