Ryan Holle of Pensacola, was convicted of first-degree felony murder in the March 2003 death of 18-year-old Jessica Snyder, who was beaten to death with the butt of a shotgun.
Holle was also convicted of burglary and robbery charges. Holle allowed his four co-defendants to borrow his car after they talked about stealing a safe from Snyder's home and beating her.
In June, Donnie Lee Williams and William Allen Junior were convicted of first-degree murder, robbery and burglary. They were also given mandatory life sentences.
The trial for a fourth defendant, Jermond Thomas is set for later this week.
The fifth defendant, 23-year-old Charles Miller Junior is accused of beating Snyder to death.
Prosecutors said they will seek the death penalty at his September trial.