CARSON CITY -- A gang member sentenced to 40 years in prison in a 2003 Las Vegas killing has been granted a new trial by the Supreme Court because of erroneous jury instructions.

Julius Bradford was a Rolling 60s gang member who was convicted in 2004 for his role in the death of Benito Zambrano-Lopez. Zambrano-Lopez was shot in the back multiple times on Rancho Drive on June 9, 2003.

The order by the three-judge panel was issued Tuesday.

On appeal, defense attorney JoNell Thomas raised a number of concerns, including the accuracy of the jury instruction, which involved whether Bradford had the specific intent to commit murder when Zambrano-Lopez was robbed.

Bradford was one of three men who attacked Zambrano-Lopez. He did not fire the gun that killed him.

The court said for Bradford to have been convicted of first-degree murder, he had to have knowingly aided the other person with the intent to kill Zambrano-Lopez.

Her argument was based on a December opinion by the court in another case that questioned whether a person could be held responsible for murder if no intent existed for the killing to take place, Thomas said in an interview after the case was heard in February.

Under a previous rule, a co-defendant could be held responsible for anything that occurred if it were foreseeable that the person intended it to happen or not, she said. The new opinion holds that the defendant has to have a certain mental state before he can be found guilty of a specific offense, Thomas said.

The court also commented on questions of misconduct by prosecutors. Although calling it a harmless error in Bradford's trial, the court nevertheless expressed concern about the Clark County district attorney's decision to introduce information about gang affiliation in violation of a court order.

The court noted that the gang affiliations also were used by Bradford's trial attorney.

"However, we caution the state that we will not tolerate further misconduct of this nature, especially in Bradford's retrial," the court said.

It also cautioned the prosecution on its misstatement on the definition of reasonable doubt presented to the jury in closing arguments in Bradford's case.

"As we have previously held, a new trial can be the appropriate remedy when the jury is improperly informed about the state's burden of proof," the court said.

Police said Zambrano-Lopez was walking home from a grocery store in the 1000 block of North Rancho Drive when three men walked up, beat him and shot him multiple times in the back.

The triggerman, Tyrone Williams, was convicted of first-degree murder.