Donald Reed "Popeye" Mazza, Public Enemy Number 1's (PENI) "shot caller" or leader, has a violent criminal history, including drug use (he was a heavy heroin user) and an attempted murder conviction.  In April 1999, according to prosecutors, only 10 hours after being released from prison, Mazza stabbed an associate, William Austin, while Dominic (Nick) "Droopy" Rizzo, the number two leader in PENI (and godfather to Austin's child), held Austin down.  Austin was a member of the Los Angeles Death Squad, another white supremacist gang, and an active participant in PENI and NLR activities.  Austin was said to have been attacked in this "prison-ordered hit" because fellow gang members believed that he was working with law enforcement as an informant.   According to prosecutors, an Aryan Brotherhood member is believed to have overseen the attack.

In 2003, Mazza was convicted of attempted murder and is currently serving 15 years in state custody at Pelican Bay, a high security state prison for hardcore gang members.  In the summer of 2005, Mazza reportedly earned his Aryan Brotherhood "dancing shoes," which means that he was inducted into the AB ranks.  He has now been validated by prison officials as an AB associate.  Mazza's new membership in AB is likely to boost PENI's position and power in California's prison system.

Dominic Peter "Droopy" Rizzo was given a life sentence for his attempted murder conviction and is locked up at West Valley Detention Center in Rancho Cucamonga.  Prior to the conviction, Rizzo had been released from the Santa Ana Orange County Jail on July 17, 2002, on a $500,000 bond paid with a cashier's check, which later turned out to be bogus.  His use of a forged document is not uncommon for PENI members, who are often involved in counterfeit schemes and identity theft.

In November 2003, while being transported, Rizzo slashed the neck of another inmate, a convicted child molester, with whom he was shackled in line.  Rizzo pleaded guilty on July 17, 2006, to assault with a deadly weapon; his sentence was added to the life term he was already serving for the attempted murder of Austin.  Prison personnel have since validated Rizzo as an AB associate.

Another key player in the PENI leadership is Devlin "Gazoo" Stringfellow, whose mother married Reuben Pappan, a significant Aryan Brotherhood member convicted in 2003 of conspiracy to commit murder.  She later allegedly divorced Pappan so that her son could spend his parole at her home and not violate his terms of probation for affiliating with other gang members.