Heather J. Mattes is an experienced criminal lawyer. She was born in Philadelphia, Pennsylvania and has lived and practiced here throughout her career. Ms. Mattes grew up in Delaware County where she attended public school and participated in the music program graduating as a national honor society member. In 2003, she was inducted into Sun Valley’s “Wall of Fame.”

Ms. Mattes attended The Pennsylvania State University where she graduated Summa Cum Laude with a degree in Communications Studies emphasizing ethics and philosophy. She graduated from the Villanova University School of Law and began her early practice as an Assistant Public Defender in West Chester, Pennsylvania for three years defending indigent clients at all levels of prosecution and in the state appellate courts.

For sixteen years, Ms. Mattes was an Assistant District Attorney in Delaware County, Pennsylvania where she tried misdemeanor and felony cases from driving under the influence to capital homicide as well as sexual assault and other special victim matters. She mentored and supervised other attorneys during her tenure.

Since 2005, Ms. Mattes has limited her practice to criminal defense in the state and federal courts. She is a member of the federal Criminal Justice Panel, the Pennsylvania Bar Association as well as the National Criminal Defense Lawyers. Ms. Mattes was a member of the Board of Pennsylvania Criminal Defense Lawyers for six years and remains active with the organization. She received commendations in 2014 and 2016 for her work with PACDL. In 2019 and 2020, Heather was the President of the Delaware County Chapter of PACDL.