Appau was born on 2 August 1951 at Badu, a town in the Tain District of the Brong Ahafo Region. He begun schooling at the Wenchi West Primary School for his primary education and proceeded to the Bekwai Methodist Middle School for his Middle School Leaving Certificate. He was in Prempeh College in 1965 but was unable to complete his studies for his Ordinary-Level certificate due to financial constraints. He dropped out of the school in 1967 and enrolled at the Ajumako Teacher Training College where he obtained his Teachers' Certificate "A". He later received his Ordinary-Level and Advanced-Level certificates as a private candidate. In 1977, he entered the University of Ghana to study Law and Political Science and graduated in 1980 with his bachelor of arts degree in Law and Political Science. That same year, he proceeded to the Ghana School of Law and completed his studies in 1982. He was called to the Bar as a Barrister and Solicitor of the Supreme Court of Ghana in December 1982.
Career
Appau begun working as a teacher by profession. He taugh in a number of schools including Droboso L/A Middle School and Frema L/A Middle School from 1971 to 1977. He also served as the headmaster of Subingya L/A Primary School. Appau became the Regional Coordinator of the then Students and Youth Task Force in the Northern Region after he was called to the bar in 1982. A year later he was appointed as the Deputy Regional Secretary for the Brong Ahafo Region. In 1983, he was nominated to receive training in Havana, Cuba for a ten-month course in International Relations. He was appointed a member of the National Investigations Committee upon his return in 1984. He resigned from the NIC in May 1985 and entered private legal practice at Barimah Chambers, Sunyani. On 1 September 1991, he was appointed a District Magistrate Grade 1 at the Sekondi District Magistrate Court. He worked as a District Magistrate from 1991 to 1995. While working as a District Magistrate, he was the supervisor of the Shama and Cape Coast District Magistrate Courts. In 1996 he was appointed a Circuit Court Judge and posted to the Aflao Circuit Court. Four years later, he was promoted Justice of the High Court and later posted to the Ashanti Region to serve as the supervising High Court Judge of the region. In 2006 Appau was elevated to the position of an Appeal Court judge. While serving in that capacity, he was appointed on 8 October 2012 as the Sole Commissioner of the Commission of Inquiry to look into Judgment Debts and other matters. He holds membership in associations locally and internationally, some of which include; the Association of Magistrates and Judges of Ghana. He has also participated in various national and international conferences and also authored a number of papers on key topics.
Appointment
Justice Appau was nominated together Justice Gabriel Pwamang by the then president, John Mahama. He was subsequently vetted by parliament on 3 June 2015 and approved by consensus on 24 June 2015. He was sworn into office together with Gabriel Pwamang on Monday, 29 June 2015.