Mack joined the Los Angeles Police Department in 1988. He first worked as a patrol officer and then as an undercover narcotics officer. Mack next moved to a late shift in West Los Angeles in 1990, where he began a relationship with Errolyn Romero, a nineteen-year-old ticket taker at the Baldwin Theatre. Mack was awarded the LAPD Medal for Heroism in 1993 for shooting a drug dealer who reportedly threatened his partner, Rafael "Ray" Pérez, with a gun during an undercover drug operation.
Bank robbery
In August 1997, Romero became employed at a Bank of America branch near the University of Southern California campus. On November 6, 1997, Mack entered the bank and claimed he wanted to access his safe deposit box. Romero admitted him to the secure area, where he threw her to the floor and robbedthe vault of $722,000. In her capacity as branch assistant manager, Romero had ordered double the usual amount of cash to be on hand at the bank on the day of the robbery. After one month of investigation, Romero confessed to her role in the crime and implicated Mack as the mastermind. He was arrested in December 1997. His two accomplices were never caught. Mack was sentenced to fourteen years and three months in prison and has never revealed the whereabouts of the money. He was released on May 14, 2010. According to the Tupac documentary entitled 'Assassination: Battle For Compton', citing official legal documents, a reliable jail informant by the name of Ken Boagni, who befriended Rafael Perez in prison, stated Perez claimed the money stolen in the bank robbery was intended to go to Harry Billups, also known as Amir Muhammed, who was friends with Mack, for allegedly carrying out the murder of late rapperChristopher Wallace, also known as Biggie Smalls because Billups was not paid in full by his contractors, namely Reggie Wright Jr. and David Kenner, because he failed to also murder Sean Combs, the second intended target. Boagni claimed both Perez and Mack were involved in the murder of Wallace, but Billups was the shooter.
Relation to the murder of The Notorious B.I.G.
In April 2007, the estate of Christopher Wallace, a rapper who performed under the name The Notorious B.I.G., filed a wrongful death lawsuit against the City of Los Angeles, which also named Mack, Pérez, and Nino Durden as defendants. The lawsuit alleged that the officers conspired to murder Wallace, and that Pérez and Mack were present the night of the drive-by shooting which claimed his life on March 9, 1997. In 2010, the Wallace family voluntarily dismissed the lawsuit and their claims against the city and the officers.