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Mark Hammer

Mark  Hammer Photo
Mark Hammer Founding Attorney
  • Bio
  • Admissions & Education
  • Employment
  • Memberships & Awards
  • Classes/Seminars
  • Involvement

Dedicated to the Fighting for Your Rights

As a founding lawyer of The Hammer Law Firm, LLC, Mark A. Hammer has built a practice that focuses exclusively on criminal defense and the client. Additionally, he draws from extensive experience and insight gained as a former prosecutor to handle each case as effectively and intelligently as possible. As a result of his talent, experience, and commitment to making a real difference in the lives of clients and their loved ones, Mark has been successful in hundreds of criminal trials at both the state and federal levels.

Mark earned his B.S. and law degree from the University of Iowa, Iowa City before spending over 13 years as an assistant prosecuting attorney in Washington and Minnesota. This experience enabled Mark to effectively gauge the other side’s actions and intentions when representing defendants and provided him with the insight he leverages in each case our firm handles.

A committed member of the community, Mark has dedicated time to pro bono representation and has volunteered for the ALS Association. He has also taught legal classes and seminars on trial advocacy and trial practice in several schools of higher education.

Mark’s extensive experience and genuine demeanor make clients feel confident in choosing The Hammer Law Firm, LLC to help them through difficult times. Be confident in choosing us. Our firm is located in St. Louis, Missouri, and serves clients throughout the metropolitan area and statewide throughout Missouri. The choice of a lawyer is an important decision and should not be based solely on advertisements. This disclosure is required by the rule of the Supreme Court of Missouri.

Litigation Percentage

  • 100% of Practice Devoted to Criminal Defense Litigation

Professional Profiles

Admissions & Education

Bar Admissions

  • Missouri
  • Minnesota
  • Washington
  • California
  • U.S. District Court Eastern District of Missouri
  • U.S. District Court Western District of Missouri
  • U.S. District Court Southern District of Illinois
  • U.S. District Court Central District of California
  • U.S. District Court Southern District of California
  • U.S. District Court Northern District of California
  • U.S. District Court of Colorado
  • U.S. District Court Southern District Indiana
  • U.S. Court of Appeals, 8th Circuit
  • U.S. Court of Appeals, 9th Circuit


  • B.S. University of Iowa
    Iowa City , IA 1984
  • J.D., Law Review: Associate Editor, Iowa Law Review, Moot Court - Case Editor (Executive Board) University of Iowa College of Law
    Iowa City , IA 1986

Past Employment Positions

  • Assistant Prosecuting Attorney
    • Ramsey County (St. Paul)
    • Hennepin County (Minneapolis)
    • King County (Seattle)
  • Associate (Civil) Attorney, Brobeck, Phleger & Harrison, Los Angeles, California
  • Airline Transport Pilot, Comair (Delta) Airlines
  • Federal Flight Deck Officer, Department of Homeland Security

Professional Associations and Memberships

  • American Bar Association
  • National Association of Criminal Defense Attorneys
  • Missouri Association of Criminal Defense Attorneys
  • Bar Association of Metropolitan Saint Louis
  • Master of the Bench, Theodore McMillian American Inn of Court


  • Selected to Super Lawyers 2017 - 2019


  • Adjunct Professor of Law: Criminal Trial Practice, Saint Louis University School of Law
  • Adjunct Professor of Law, Criminal Trial Advocacy, William Mitchell College of Law
  • Faculty Member, National Prosecution Advocacy Center, University of South Carolina, Advanced Trial Advocacy

Pro Bono Activities

  • Represented Death Row Defendant on Capital Appeal to Cal. Supreme Court, sentence commuted to life imprisonment

Community Involvement

  • Mark is a volunteer for the ALS Association and is actively involved in the mission to find a cure for ALS (Lou Gehrig's Disease)

Contact Us Today

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Hear From Our Happy Clients

At The Hammer Law Firm, LLC, your satisfaction is our priority! See for yourself what our clients have to say about working with us.

    "We are happy that we chose The Hammer Law Firm"

    Our situation was handled ethically, honestly, and professionally. Mr. Hammer was available to us throughout the case and answered promptly when we had questions or concerns.

    - Former Client

    Mr. Hammer and Raj were there to ease the scare. From a felony to a simple misdemeanor fine ... it was a true miracle and if you think there is no hope then this is the firm to contact.

    - R.T.
    "Mark Hammer is a decisive, direct, and conscientious attorney. I would definitely recommend him to others."

    As soon as we entered the courthouse, I observed that he went out of his way to interact with everyone he came into contact with. This attentiveness towards other people gives him the unique ability to look into the perspectives of all involved on both sid

    - Former Client