Annie Dookhan worked as a chemist in a Massachusetts state drug lab for nine years, and is now accused of lying about receiving a master's degree in chemistry.  When Dookhan formerly worked as a chemist, she handled evidence for thousands of drug cases.
The State of Massachusetts is accusing her of doctoring evidence to change test results. Dookhan's alleged tampering calls into question at least 34 thousand cases going back to 2003, and in some cases, may have wrongfully convicted the innocent.
CNN's Susan Candiotti reports.