Mary-Scott "Scottie" Gates Hennigan has been an active part of Gates Law since the fall of 2000. Beginning as a part-time legal assistant while she completed her undergraduate degree at VCU, where she became inspired to attend law school and join the family practice.

While in law school, Mrs. Hennigan spent a year interning with the Office of the Commonwealth's Attorney for the City of Virginia Beach and gained a vast amount of experience, both in the courtroom, prosecuting cases, and in the area of legal research, drafting appellate briefs. Upon graduating and being admitted to the Virginia State Bar, Scottie began working for a small law firm in Virginia Beach.

In 2010, she moved back to Richmond with her husband and young daughter and began working part-time at Gates Law Offices. Shortly after her second child was born, she went back to work full-time at Gates Law, splitting her time between the Chesterfield and Amelia locations.

In 2018, Mrs. Hennigan became the Managing Partner at Gates Law Offices, PLLC.