Johannes Lopez was convicted of multiple crimes by a Georgia jury. The crimes included “street gang terrorism” as well as more traditional counts of assault and firearms offenses.

Lopez attempted to present expert evidence to counter the testimony of prosecution experts that Lopez committed gang-related crimes. The trial court excluded the testimony of the defense expert. The Georgia Court of Appeals reversed the conviction after concluding that the defense had a right to present relevant expert testimony.

Facts of the Case

The criminal charges arose out of two incidents. In the first, a Ford Explorer rear-ended a car and then drove away. The occupants of the car chased the Explorer. After obtaining the license plate number, the car occupants continued to follow the Explorer, which eventually pulled into a parking lot. The occupants testified that two people in the Explorer jumped out and shot at them. Nobody was injured. The Explorer was registered to Lopez’ mother.

About thirty minutes later, a Nissan Altima passed a Ford Explorer. Occupants of the Altima testified that shots were fired at the Altima from the Explorer. Nobody was injured.

The occupants of the Altima called 911. Responding to that call, police officers in Cobb County pulled over the Explorer. Lopez was the vehicle’s only occupant.

Lopez was armed with a handgun. Since he was a convicted felon, there was ample evidence upon which to base a firearms violation. The prosecution also charged Lopez was aggravated assault for participating in the shootings. All of those offenses, if proved, would have subjected Lopez to serious penalties, but the prosecution decided to pile on additional counts of “street gang terrorism.”

To prove that Lopez committed the Georgia crime known as “street gang terrorism,” the prosecution needed to present evidence that (1) Lopez was a member of a street gang, and (2) the crimes constituted “criminal gang activity.” Georgia defines a “street gang” as “group of three or more persons” that “engages in criminal gang activity.” The commission of specified violent crimes, as well as tagging, constitutes criminal gang activity.

Prosecution Experts

Whether an individual belongs to a “group of three or more persons” is a question of fact that may not need to be proved by expert testimony. Any time three or more people work together to commit an offense specified in the statute, they are by definition members of a street gang. Proving that the individuals decided to commit the crime together may be all the evidence that is needed to prove the crime of street gang terrorism.

Since Lopez was not in the company of two other people when the police stopped the Explorer, proof that the shootings were committed by a street gang was more problematic. The prosecution relied on several expert witnesses to prove that Lopez was part of a gang and that his conduct constituted gang activity. Those experts “discussed the culture and activities of the criminal street gang, SUR-13, as well as Lopez’s affiliation with the gang.”

The experts also testified that the crimes furthered the interests of SUR-13. Their ability to discern what motivated the crimes is suspect, as even the best experts cannot read minds.

Lopez attempted to call his own gang expert. Remarkably, the trial court refused to allow the expert to testify. After he was convicted, Lopez based his appeal on the unfairness of allowing only side in the case to present expert testimony.

Defense Expert Qualifications

The defense expert was an attorney who formerly belonged to a gang. The best “gang experts” are often former gang members who have inside knowledge of how gangs work. Prosecutors, on the other hand, tend to rely on the dubious expertise of police officers who have an outsider’s perspective on gangs.

The defense expert had the same credentials as law enforcement experts, in that he had investigated and prosecuted gang members, including SUR-13, while working in a district attorney’s office. More importantly, he had firsthand knowledge of gang tattoos, symbols, and terminology that he acquired in and out of jail as a gang member and later in the course of professional and civic duties.

The prosecution argued that the defense expert was not qualified because he had no formal training with regard to gangs. The appellate court rejected that argument because experts do not necessarily need formal training to acquire relevant expertise. Particularly when the subject of expert testimony is not based on science, an expert’s specialized knowledge can come from informal study or experience rather than a formal education.

Membership in and association with gangs is likely to give an expert more knowledge of gang practices than typical jurors will have. Former gang members who gain first-hand knowledge of gang practices usually have more knowledge than police “experts” who acquire information by attending agenda-driven seminars taught by law enforcement agents who have never been part of a gang and who have no personal knowledge of gang culture. The appellate court correctly decided that the expert was qualified.

Relevance of Defense Expert Testimony

The trial court also found that the defense expert had no relevant knowledge of SUR-13. According to the prosecution, the expert only had knowledge of a Florida gang that he joined in the 1970s.

The defense made clear that their expert had relevant knowledge. His personal experience, coupled with his work as a prosecutor and his participation in public outreach programs, qualified him as an expert on gang culture and activities. He did not need to belong to SUR-13 to understand how street gangs operate.

Remarkably, the prosecution argued that the defense expert had nothing relevant to say despite relying on an expert in street gangs who testified in general terms about their culture and activities, without offering any specific testimony about SUR-13. The appellate court did not countenance the hypocrisy of allowing an expert to testify for the prosecution while disallowing testimony on the same subject matter by an expert for the defense.

The prosecution experts all testified that Lopez’s actions were related to gang membership because they occurred in public and were triggered by hostility to the color red, a color that represented a rival gang. Those speculative conclusions about what motivated Lopez to shoot hardly constitute reliable expert testimony.

The defense expert would have countered that testimony by explaining that gang members do not usually attack unsuspecting strangers, that doing so violates the code governing gang activities, and that attacking an innocent person who is not affiliated with a rival gang diminishes a gang member’s status within the gang. He would also have explained that gang members who wanted to send a message to the public would not have taken action in the darkness at 1:30 a.m. on streets where few people were present.

The court concluded that the defense had just as much right as the prosecution to present expert testimony. Denying that right prevented Lopez from countering the prosecution’s dubious expert testimony and thus deprived Lopez of a fair trial. His conviction was therefore reversed and his case was remanded for a new trial on the street gang terrorism charges.