Dr. Ehrhardt's main interests are in the areas of forensic biology, microbiology, and trace evidence analysis. He currently maintains a microbial culturing facility that he uses to investigate the chemical and biological signatures associated with the production process of illicitly-grown bacteria (e.g., Bacillus anthracis, Yersinia pestis). Dr. Ehrhardt's lab also works on developing new methods for analyzing complex cell mixtures that are recovered as evidence from a crime scene. Sample types range from bacterial communities within complex matrices to human cell mixtures recovered from â??touch' and trace biological samples.