Effective representation of a criminal defendant facing charges based on DNA evidence requires an attorney investigate the crime lab and the analysts who performed the testing. An effective investigation of a crime lab includes a thorough review of all corrective action files, review of 5 years of proficiency test results and underlying data as well as review of all reports of audits conducted on the laboratory during the relevant time period. This presentation will describe each of these documents and provide legal support for obtaining them. Given the national media attention on the many serious problems being discovered in crime labs around the country, it should be apparent that these documents are essential to the effective representation of a criminal defendant.