Humans make mistakes. We miss things, get confused, and misremember details. That is why the rules for handling forensic evidence in a criminal case are very strict and dictate how materials pass through police hands.
The strict procedure is meant to ensure the quality of convictions, and it allows defendants to challenge admission of evidence that is admitted against them without proof that proper procedure was followed. Now legislators in Illinois are considering a new law that would allow state crime labs to hide mistakes that technicians make, according to defense attorneys. Police say that the law ensures quality results. Let's consider the controversy reported by ABC News.