Jurors convicted Pedro Espinoza in the 2008 murder of the 17-year-old. Now, they are weighing whether to sentence him to death. Espinoza's gang affiliation makes him eligible for the death penalty.
Prosecutors have asked for the death penalty, but the defense wants life in prison without parole.
Testimony is expected to resume on Tuesday.
Shaw was gunned down after leaving a friend's house in 2008. He was confronted by Espinoza, who thought he was a member of a rival gang.