The jury was also warned against using threats or coercion to try to change anyone's mind, The Arizona Republic reported.
Johnathan Doody, 39, was 17 when he was arrested in 1991, two months after six monks, a nun and two acolytes were killed at the temple in a Phoenix suburb. Prosecutors said he and Alessandro "Alex" Garcia, who pleaded guilty, set out to rob the temple, killing any potential witnesses.
The current trial is Doody's third.
A juror was dismissed Wednesday, and another woman who remained on the jury complained her fellow jurors were trying to override her opinions.
Superior Court Judge Joseph Kreamer told jurors to keep their discussions "open and free." He also said jurors should follow their own opinions about the case.
"You are forbidden from engaging in any coercive or threatening conduct which may cause another juror to vote against his or her will or contrary to his or her true belief," Kreamer said.