A proposal to allow alleged perpetrators of the 9/11 attacks to plead guilty and avoid the death penalty poses a powerful dilemma for victims' families, some of whom still want to seek the ultimate retribution after two decades of legal limbo.

The proposal detailed by prosecutors in a letter this month could offer families of the nearly 3,000 victims the best path to a resolution of a case bogged down in pretrial maneuverings in the Guantanamo military commissions for years — and with no end in sight.

For some families of those killed in New York's World Trade Center, the Pentagon, and in Pennsylvania say a deal without a trial could mean the entire truth about what happened on September 11, 2001 might never be told.