Book excerpt: Conduct an investigation into the world of forensic science. Understand why the law determines which evidence may or may not be used; discover just how accurate--or inaccurate-- lie detectors are; take a tour of a police crime lab; learn how insects and plants affect a cause-of-death analysis; note the similarities and differences in analyzing fibers and hairs, drugs, soil, glass, and firearms; examine the history behind fingerprinting; remember that an investigator's ultimate weapon is information.