In October 2002, John Allen Muhammad and Lee Boyd Malvo terrorized the Washington beltway area with a series of sniper shootings that killed 10 people and wounded three more. They were also connected to at least 12 other shootings in the months leading up to the sniper attacks, some of them fatal.
Malvo, who was 17 at the time, faced trial in Virginia and was found guilty for some of the murders, and sentenced to life in prison without parole. In 2004, he pleaded guilty to two more charges of murder and attempted murder in an effort to avoid the death penalty.
Once the Supreme Court ruled in 2005 that juveniles were not subject to the death penalty, that issue became moot, but Malvo later also pleaded guilty to six more murders in Maryland. He was sentenced to six consecutive life sentences without parole.