Donald J. Cosley

Donald J. Cosley is a seasoned Illinois attorney who has represented clients since 1994. He focuses on divorce, family law, criminal defense, DUI, traffic violations, and driver’s license reinstatement matters at the Law Offices of Donald J. Cosley. Admitted to practice in Illinois, the U.S. District Court for the Northern District of Illinois, and the U.S. Supreme Court, he delivers strong and strategic advocacy. He is known for providing responsive service and clear guidance to individuals facing complex legal challenges. He protects clients’ rights carefully at every stage.

Mr. Cosley earned his J.D. from John Marshall Law School in 1994. During law school, he developed a strong foundation in litigation, legal research, and courtroom procedure. He also holds a B.A. from DePauw University in Greencastle, Indiana, completed in 1991. His academic training prepared him to analyze complex disputes, apply the law accurately, and advocate effectively for clients in both state and federal courts. He continues to build on this knowledge through ongoing professional development and legal education programs.

Mr. Cosley has handled a wide range of family law matters, including divorce, custody, visitation, and child support disputes. In criminal defense cases, he represents individuals charged with DUI, traffic offenses, and white collar crimes. His approach is thorough and detail-oriented, allowing him to evaluate evidence, identify defenses, and pursue favorable outcomes. Clients benefit from his steady guidance, practical advice, and commitment to protecting their rights throughout the legal process. He works diligently to resolve matters efficiently and with integrity.

Donald J. Cosley is active in respected professional associations, including the Illinois State Bar Association and the Northwest Suburban Bar Association, in addition to his casework. He has served in numerous leadership roles, such as President, Vice President, Treasurer, Secretary, and Chairperson of key committees. These positions reflect his dedication to the legal community and high professional standards. His recognition as an Elite Lawyer and other honors further demonstrate his commitment to excellence in legal practice. He upholds strong ethics in every matter.

Law Office Affiliations

• Partner, Law Offices of Donald J. Cosley
• Member, Illinois State Bar Association
• Member, Northwest Suburban Bar Association (NWSBA)
• Member, Chicago Bar Association
• Member, National Association of Criminal Defense Lawyers

Licensed State

• Illinois

Education

• John Marshall Law School
  Juris Doctor (JD)
• DePauw University
  Bachelor of Arts (BA)

Awards & Badges