He was first seen at the station, where Martin Riggs was making a bet that he could free himself out of the straightjacket. After Riggs frees himself, Estaban and all the others put their money on the table for Riggs, having won the bet, at the same Roger Murtaugh told them to get back to work.
The next day, Estaban is seen again at the station after Murtaugh was ambushed the previous night by Vorstedt and his henchmen. They all arrive at Rudd and Vordstedt's stilthouse to arrest them and the rest of the henchmen there, but the arrest didn't go as planned as they revealed themselves to be diplomatic agents.
After the murders on detectives Tom Wyler, Meagan Shapiro, Jerry Collins, Tim Cavanaugh, Friesen, and Moss, Estaban was later seen again at the precinct being given the orders by Captain Ed Murphy to get ahold of Riggs and Murtaugh before anything is done to them.
Estaban isn't seen for the rest of the film, but it is implied that he's still working on the krugerrand case and maybe watching over Leo Getz until the federal marshal comes for him while Riggs and Murtaugh go after Rudd and Vorstedt at the Alba Varden cargo container ship.
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