<p>A 20-year-old who admitted taking part in the 2002 beating death of his grandfather and attacking his grandmother during a robbery has been sentenced to life in prison.</p><p>Justin Kelly Thomas pleaded guilty Thursday to armed robber and murder in the death of Doyle Thomas, 84. District Attorney Garry Moss, who had planned to seek the death penalty, said Thomas admitted to the details of the attack, in which Ella Thomas, 82, was badly injured.</p><p>Investigators said Lantak Vantress Williams, 20, of Powder Springs, Bryan Mario Parague, 21, and Thomas, both of Austell, went to the couple's house the night of Oct. 19, 2002 with a 9mm pistol and a shotgun to rob them.</p><p>A bank video the next day showed Thomas attempting to cash a $50,000 check from his grandfather's stolen checkbook.</p><p>Williams pleaded guilty to burglary and aggravated assault in April and was sentenced to 10 years in prison. Parague is awaiting trial.</p>
