The eldest of the Lopez siblings, Jay is Ella's brother and is supposedly the only respectable one among them. He works as a diamond authenticator, and secretly works with Fahrid Nasser to "clean" his stolen diamonds, removing the serial numbers. This allowed Fahrid to sell the diamonds back to the owners that he fake-stole them from, letting Fahrid sell the diamonds back for his share of the money while the owners got the insurance payout.
Jay was working in Fahrid's stashroom when Fahrid was killed. All Jay saw was the killer's red wingtip shoes, which was enough for the police to identify the killer: Fahrid's partner, Don Zeikel. Don took Jay hostage and threatened to kill Ella, and Maze killed Don.
The diamonds that Fahrid stole "disappeared", and Jay later went back to recover them. Lucifer was waiting and Jay explained that he became a crook to support his family. he offered to tell Ella the truth, but Lucifer threatened him to keep him silent because the information would hurt Ella's faith in her older brother.
