Mark was born and raised in St. Louis, Missouri. At the Onder Law Firm, Mark is primarily involved with products liability, medical malpractice, and general personal injury litigation. Mark also handles select criminal defense matters generally involving white collar crime.

Mark spent a significant portion of his career with the United States Attorney’s Office for the Southern District of Illinois. At the U.S. Attorney’s Office, Mark split his time between the defense of civil litigation (to include medical malpractice, personal injury and employment discrimination suits against the Government) and criminal prosecution of complex conspiracy cases.

Prior to serving as an Assistant United States Attorney, Mark worked as a litigator with a private firm, and as an Assistant Circuit Attorney in St. Louis City where he prosecuted violent crimes, including homicide. Mark also served as an Assistant Professor at the University of Missouri - St. Louis, where he instructed criminal law courses.

Mark has tried more than 40 civil and criminal jury trials to completion. During law school at Northwestern University, Mark won the Mock Trial National Championship and was recognized as the Best Oral Advocate in the United States.