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.
More top news
Justin Bieber has posted a video online apologising for his "arrogant" and "conceited" behaviour in the past year.
More than a third of children in England are considered overweight, a new 20-year study suggests.
The Tory party's "anti-immigration rhetoric" could cost MPs key marginal seats in the forthcoming general election, a new report says.