Robert Marquez, a 55-year-old Hispanic man, was shot and killed on June 9, 2018, while working as a security guard in north Houston. Marquez owned a private security company and was patrolling near a townhome complex when he encountered a man wearing a skeleton mask who was attempting to rob him. The suspect fled in a white Ford Expedition and Marquez pursued; during the chase one of the SUV’s occupants shot Marquez while he was on the phone with 911.

A memorial was placed at the location where he was shot. The Houston Police Department released surveillance photos of the vehicle and asked for tips. Marquez’s widow Sara said he often prepared his family for the dangers of his work, and family members remember his commitment to making the neighborhoods he patrolled safer.

Courtney Chatmon, a 30-year-old man, was later arrested following an unrelated felony evading arrest and charged with Marquez’s murder in the 182nd State District Court; he remains in custody. Does anyone have information about the white Ford Expedition or the events that night?