Leslie is a defense attorney in Los Angeles. He was able to get a verdict of "not guilty" for Copperhead which leads to Kate Spencer's first appearance as Manhunter
For more information see: Street Justice
Copperhead hires Leslie, to defend him in the case of killing at least 15 people and eating many of them. Leslie uses the defense that Copperhead is not guilty by reason of Genetic Anomaly. This plan works and Copperhead gets off for those murders.