Does forensic evidence really matter as much as we believe? New research suggests no, arguing that we have overrated the role that it plays in the arrest and prosecution of American criminals. A study, reviewing 400 murder cases in five jurisdictions, found that the presence of forensic evidence had very little impact on whether an arrest would be made, charges would be filed, or a conviction would be handed down in court. A mere 13.5 percent of the murder cases reviewed actually had physical evidence that linked the suspect to the crime scene or victim.