Dean concentrates his practice in the area of professional liability. Prior to his joining Marshall Dennehey in 2008, Dean worked for a Bucks County, Pennsylvania, law firm where he served as a plaintiff's attorney in complex medical malpractice and personal injury cases. As well, from 2001 to 2005, Dean served as a prosecutor and ultimately as a Deputy District Attorney in the Bucks County District Attorney's office, where he tried numerous criminal jury and bench trials and worked closely with state and local law enforcement agencies in a broad variety of criminal investigations.

In 1993 Dean received his B.A. from Syracuse University. Thereafter, he attained his Juris Doctorate from Villanova University School of Law in 1997. Following law school, Dean was commissioned a Second Lieutenant in the United States Marine Corps. After completion of Officer Candidates School that same year, Dean served on active duty as a Judge Advocate representing service members in court martials and administrative proceedings at Marine Corps Air Station Cherry Point, North Carolina.
 
In June 2007, Dean was ordered back to active duty. He served one combat tour in Iraq with the 6th Engineer Support Battalion (Forward) as Adjutant and Assistant Operations Officer, between August 2007 and March 2008, at Camp al Taqaddum, in al Anbar Province. Dean's military awards and decorations include two Navy-Marine Corps Commendation Medals, the Navy-Marine Corps Achievement Medal, the Iraqi Campaign Medal, the Global War against Terrorism Medal, and the Sea Service Deployment Medal.

In addition to his legal practice, Dean founded and continues to be involved in the American Veterans Legal Services, a Pennsylvania non-profit corporation providing free legal assistance to eligible military veterans.