BOISE, Idaho (AP) — Joseph Edward Duncan III has been sentenced to death for the 2005 kidnapping, torture and murder of a northern Idaho boy after the federal jury deliberated just three hours.

The jurors' recommendation was binding on U.S. District Judge Edward Lodge, who thanked them, dismissed them and then issued the sentence Wednesday. Duncan showed no reaction, but he did smile as the verdict was passed to the judge.

Duncan acted as his own attorney but had offered no response to prosecutors' argument that he deserves execution after the torment he inflicted on Dylan Groene (GROAN'-ee). The boy's younger sister also was kidnapped and sexually abused but survived.

Duncan pleaded guilty in state court to killing the children's mother, brother and the mother's fiance.