In recent years, there have been three civilian firing squad executions in the U.S., all in Utah. Gary Gilmore uttered his famous final words, "Let's do it," on Jan. 17, 1977, before his execution, which ended a 10-year moratorium on the death penalty.
Convicted killers John Albert Taylor in 1996 and Ronnie Lee Gardner in 2010 were also put to death by firing squad.
Utah is phasing out its use, but the firing squad remains an option there for inmates sentenced prior to May 3, 2004.
Oklahoma maintains the firing squad as an option, but only if lethal injection and electrocution are deemed unconstitutional.
In Wyoming, Republican state Sen. Bruce Burns said death by firing squad would be far less expensive than building a gas chamber. Wyoming has only one inmate on death row, 68-year-old convicted killer Dale Wayne Eaton. The state has not executed anyone in 22 years.
Jackson Miller, a Republican in the Virginia House of Delegates, is sponsoring a bill that would allow for electrocution if lethal injection drugs are not available.
Miller said he would prefer that the state have easy access to the drugs needed for lethal injections. "But I also believe that the process of the justice system needs to be fulfilled."