Executed

John Allen Muhammad and his stand-in son, Lee Boyd Malvo, took the lives of 10 people in 2002.

Clarence Ray Allen's revenge against those who put him behind bars led him to be sentenced to death.

Serial killer Aileen Wuornos was sentenced to death after confessing to the murders of seven men.

Gary Gilmore murdered two people in Utah and was shot by a firing squad in 1977.

Karla Faye Tucker's death sentence sparks an international debate as many feel she is reformed.