Baca acknowledged last year that his second-in-command, Paul Tanaka, has a Vikings tattoo. Tanaka has said the Vikings was a nickname for deputies assigned to the Lynwood station and did not represent anything sinister.
Some argue that the groups are not inherently problematic, providing cops working a dangerous job with camaraderie and emotional support. Experts say cliques become a problem when they push officers to put their comrades ahead of the law and department policy.
What investigators are most concerned about with the Jump Out Boys isn't the alleged matching tattoos, but the suspected admiration they show for shootings. Officer-involved shootings are expected to be events of last resort.
Maria Haberfeld, a professor at John Jay College of Criminal Justice in New York who specializes in police ethics and training, said joining police subcultures makes officers "vulnerable to be compromised by group think and group pressure." Tattoos that further distinguish officers involved in shootings, she said, are particularly problematic.
"Even though they are authorized to use deadly force, I don't think it's a cause for celebration," she said. "When you reach a point in your career that you have no choice but to use deadly force, if anything it's incredibly traumatic for the shooter. It's a little bizarre to commemorate a tragic event."