Mary Karen Zahn, a native of Brownsburg, Indiana, attended Brownsburg High School and earned her B.A. from Hanover College and her J.D. from the Indiana University School of Law - Indianapolis. She joined the firm in 2001.

She focuses her practice on criminal defense, representing accused individuals in all types of criminal cases including murder, robbery, burglary, fraud and forgery, sex offenses, narcotics possession and dealing, battery, domestic battery, criminal recklessness, neglect of a dependent, theft, and alcohol related offenses, including DUI. Additionally, Zahn also represents juveniles in delinquency matters. She practices throughout the State of Indiana.

She is a member of the Indiana State Bar Association and the Indianapolis Bar Association, and has written for the Indiana Lawyer, a statewide legal publication.

In 2010, she was recognized by Indianapolis Monthly and Law and Politics magazines among the Rising Stars in the area of criminal defense.