 He's testified in 23 trials; consistently for criminal defendants charged with rape, murder or both, claiming the DNA evidence against them was unreliable because of contamination.He also admitted making the same cross-contamination error he criticized the LAPD, State Department and Cellmark's lab had made in prior years, at his own lab as well.He also admitted the LAPD's crime lab has more safeguards in place against contamination than his own lab.