As a direct result of the United States Supreme Court's 1963 decision in Gideon v. Wainwright, the 1968 Pennsylvania Constitution established the position of Public Defender as the only appointed county officer in each county. The duties of the Public Defender are outlined in the "Public Defender Act" in the County Code. The Public Defender is responsible for furnishing legal counsel to those accused in Criminal Court who lack sufficient funds to retain their own counsel. The Public Defender also provides representation in other proceedings where free counsel is a recognized constitutional right.

The Public Defender Office is located on the third floor of the East Wing of the Court House. In addition to the Chief Public Defender, there are 9 Assistant Public Defenders. All are employees of Cumberland County. The Public Defender Office handles more than 3 thousand cases a year. All types of cases are defended, from disorderly conduct to capital murder. Criminal cases are handled from the first filing of charges to the end of the last appeal. Representation is also provided for juveniles in Juvenile Court, for individuals charged with contempt for noncompliance with Court Orders (i.e., support cases), and for those on probation or parole who are threatened with revocations.

The Chief Public Defender is appointed by the County Commissioners. The Chief Public Defenders who have served Cumberland County since the creation of the office are:

• Hon. Edgar B. Bayley (1968)
• Hon. George E. Hoffer (1968-1976)
• Hon. Sylvia H. Rambo (1976)
• Taylor P. Andrews, Esq. (1976-2010) 
• Timothy L. Clawges, Esq. (2011-2015) 
• Michael Halkias, Esq. (2015-present)