A state appeals court on Wednesday overturned the conviction of a man who once was sentenced to death in the 1991 slayings of four teenage girls, sending the case back to a lower court because of a codefendant's statement that was used by prosecutors.

Robert Springsteen IV, who was 17 at the time of the killings, was convicted in 2001. His death sentence was commuted to life in prison after the U.S. Supreme Court ruled that it was unconstitutional to execute killers who were under the age of 18 when the crime was committed.

On Wednesday, the Texas Court of Criminal Appeals voted 5-4 to reverse Springsteen's conviction and sent the case back to a Travis County court.

Eliza Hope Thomas, 17; Amy Ayers, 13; and sisters Jennifer and Sarah Harbison, ages 17 and 15, were killed during the 1991 yogurt shop robbery. The girls were bound, gagged and shot in the head, and the store was set on fire, authorities said.

Springsteen and co-defendant Michael Scott were convicted based on confessions that also implicated each other.

Each man's statement was introduced at the other's separate trial, even though both men exercised their Fifth Amendment right against self-incrimination to avoid testifying. Both men accused police of coercing the confessions.

Defense attorneys argued that the fact that they could not cross-examine the men about the statements violated their clients' Sixth Amendment rights.

"We cannot say, without a reasonable doubt, that the admission of Scott's statement did not affect the jury's determination of appellant's guilt," the court majority ruled in an opinion by Judge Paul Womack.

The court did not address Scott's conviction.

There was no immediate response to calls seeking comment Wednesday from Travis County District Attorney Ronnie Earle and a lawyer for Springsteen.