Sreto Crnjak was born in 1953 in Mosorovići. He graduated from the Law School in Sarajevo in 1976 and passed his bar exam in 1980. His first work experience was at the Legal Service of the FAMOS Engine Factory Sarajevo where his duty was to “represent the Company before courts“. He was a judge of the Court of Associated Labor in Sarajevo, judge of the High Court in Sarajevo (RS), judge of the District Court in Istočno Sarajevo, the President of the District Court in Istočno Sarajevo, and judge of the Cantonal Court in Sarajevo. He was a member of the Bar Examination Board of Republika Srpska as examiner for Constitutional Law and Organization of Judiciary, and a member of the Examination Board for Misdemeanor Court Judges of Republika Srpska as Misdemeanor Law examiner.

He was appointed judge of the Court of Bosnia and Herzegovina on 18 January 2007, and he took office on 1 March 2007. For two years he was a member of the Commission for Bar Examination of Bosnia and Herzegovina as a Constitutional Law examiner. He co-authored the Intellectual Property Reference Book for Judges and Prosecutors (the topic of Patents). He authored the following papers in the field of Administrative Law: Open Issues in Administrative Proceedings in Bosnia and Herzegovina (Otvorena pitanja upravnih postupaka u Bosni i Hercegovini), Oral Public Hearing in Administrative Dispute (Usmena javna rasprava u upravnom sporu), and Validity, Finality and Enforceability in Administrative Proceedings (Pravosnažnost, konačnost i izvršnost u upravnom postupku). He periodically lectures at the Center for Education of Judges and Prosecutors of the Federation of Bosnia and Herzegovina.