JACKSONVILLE, Fla. -

Channel 4 has learned that the State Attorney's Office is pursuing the death penalty against 21-year-old James Rhodes. 

Rhodes waived his first appearance in court Wednesday afternoon after being arrested Tuesday on charges of murder and aggravated assault with a deadly weapon. 

Investigators said Rhodes is the man who robbed the Brentwood Metro PCS store Saturday night and fatally shot the clerk on duty, 20-year-old Shelby Farah. 

Hours after Rhodes waived his first appearance, a grand jury indicted him on first degree murder charges, which means the death penalty could be put on the table.

"Ms. Corey, right now, is focusing on, showing the grand jury enough evidence to establish first degree murder so she can therefore go for the death penalty," said Defense Attorney Gene Nichols. "That felony that he committed, robbing her with a firearm and then killing her, not only gives Ms. Corey enough to go to a grand jury to suggest a first degree murder case punishable by death, but it appears it was committed cold, calculating, with multiple other aggravators at play."

Shelby Farah Farah's mother, Darlene, told Channel 4 the maximum punishment will be the only justice for her daughter's death.

"I'm going to make sure, even if it takes the last breath in my body, he needs to get the death," said Farah.

Nichols warns that there are many legal hurdles ahead for Farah's family, including mitigating factors and character witnesses for Rhodes. He points out that because Rhodes is so young, his age could weigh on the jury. 

"Is it going to be more difficult to get a death penalty against a young person than it would be someone 30 or 40 or 50? Sure. A jury is going to take his age into account," said Nichols.

Rhodes is scheduled to be arraigned August 14 and is being held in the Duval County jail without bail.