Oscar Benvenidez is the accomplice of drug dealer and murderer Reggie Mathis. Mathis shot informant Kevin Stanton and killed his friend Sara Teasdale. Benvenidex tried to call for an ambulance, but Kevin’s handler, Detective Mark Rivera, called off the response, hoping his career would be saved if Kevin died.
Kevin lived, and when Mathis and Benvenidez were tracked, Benvenidez gave himself up for a deal. With his and Kevin’s testimonies, Rivera was threatened with a manslaughter charge into testifying against Mathis, and when Rivera’s career was destroyed, Mathis was imprisoned.
Benvenidez pleaded guilty to lesser charges regarding his involvement in the shootings and received a reduced sentence. (L&O: "Bait")