In its unanimous decision, the court upheld the murder convictions against Clayton Jerrod Ellington but sent the case back for a new sentencing trial, The Atlanta Journal-Constitution reported.
When Ellington was sentenced to death in 2008, it was the first capital sentence imposed by a DeKalb County jury in nearly 20 years.
Among other things, Justice David Nahmias said the trial judge incorrectly barred Ellington's lawyers from asking prospective jurors if they would only the death sentence, not life in prison, for the murder of two children.
"We believe that Ellington was entitled to ask whether the prospective jurors in this case would automatically vote for a death sentence in any case in which two murder victims were young children, regardless of any other facts or legal instructions," Nahmias' opinion said. "As to the jury's decision on the sentences in this case, our experience in criminal justice matters and simple common sense indicate that the fact that two of the victims were young children was the critical issue."
Ellington was convicted of using a hammer in the May 2006 beating death of his wife, Berna Ellington, and their twin children, Christian and Cameron.