Dan Leonard served as one of O.J. Simpson's defense attorneys in the civil wrongful death trial, working alongside lead counsel Robert Baker and Robert Blasier. He carried a substantial workload during the pre-trial phase, conducting depositions of key figures in Simpson's inner circle — including Allen Cowlings, Jason Simpson, Faye Resnick, and Marcus Allen — and cross-examining witnesses such as Karen Crawford, Det. Ronald Phillips, and Dennis Fung at trial. During the defense's closing argument, Leonard delivered the portion attacking the credibility of the plaintiffs' paid expert witnesses, complementing Blasier's broader assault on the physical and DNA evidence.