Prof. Kessy holds a Bachelor of Arts degree in Political Science and Public Administration, a Master of Arts in Public Administration degree from the University of Dar es Salaam, and a Doctor of Philosophy in Development Policy and Management from the University of Manchester (UK). Between 2000 and September 2018, he worked at the Department of Political Science and Public Administration as a Senior Lecturer at the University of Dar es Salaam before joining the University of Dodoma in 2018. In 2019, he was appointed Director of Research, Publications, and Consultancy at the same university until 2023. He has been the Deputy Principal of Planning, Finance, and Administration at the Law School of Tanzania (LST) since 2023.

Prof. Kessy has served as a consultant in numerous fields, including public administration, local governance, and others. Prof. Kessy has over 20 years of extensive teaching, research, and consulting experience. Governance, human resources, development policy and management, public administration, organization theory, climate change, and human security studies are his areas of expertise. He has also carried out major research and consultancies funded by various local and international organizations such as the European Commission (EU); Embassies of Sweden and Finland in Tanzania; Research and Poverty Alleviation (REPOA); Swiss Development and Cooperation Agency (SDC); The African Studies Centre, Leiden, Netherlands; UNFPA; UNESCO; WHO, PACT Tanzania; Danish Institute for International Studies (DIIS); the First Vice President Office (FVPO) Zanzibar; Strategic planning, evaluation studies, baseline surveys, management and evaluation, institutional analysis, local government, and election management and monitoring have been the primary foci of the majority of research and consulting services. He has also served in various committees and on special assignments by the government.

Prof. Kessy has published book chapters, articles in scholarly journals, and research reports.