RALEIGH, N.C. — A teenager convicted of killing a Raleigh city employee will spend the rest of his life in prison.

A jury decided Monday not to give 19-year-old Dwight McLean the death penalty. McLean was involved in a late-night robbery two years ago that resulted in the death of Robert Saiz.

Prosecutors say McLean shot Saiz in the back as he ran from a public utilities building. McLean was 17 at the time of the murder. Under state law, he could have been sent to death row.

"Only in case where law enforcement was killed or very old person was brutally killed by a teenager would we even consider it," district attorney Sam Currin said.

The U.S. Supreme Court is now considering whether executions are unconstitutionally cruel.

"When states execute people who commit crimes as children, they're engaging in immoral behavior," said David Mills, of the Common Sense Foundation. "They're not recognizing that people who can't fully control their impulses should not be held to the highest standard of punishment."

Officials said 184 inmates are currently on death row in North Carolina. Four of them were 17 at the time they committed murder.

"To be honest with you, I don't see much difference between a 17- and an 18-year-old," Currin said.

If the Supreme Court decides there is a difference and bans the death penalty for anyone under 18, the state may have to re-sentence the four men who were 17 when they killed.

The Supreme Court will likely issue a ruling on teen executions next spring. There are 19 states who allow the death penalty for 17-year-olds. North Carolina has never put to death a killer who was 17 at the time of a murder.