If Sigmon's execution moves forward, he will become the first inmate in South Carolina executed by firing squad in modern history and the fourth in the U.S. since 1977.

South Carolina plans to execute its first prisoner by firing squad on March 7 inside the same death chamber it's used for dozens of other executions. Firearms experts say that could be risky.

A South Carolina man on Friday is set to become the first person in more than a decade in the U.S. to be executed via firing squad. Brad Sigmon was convicted in the 2001 murders of his ex-girlfriend's parents.