Dr Ciaran McCullagh was born in Crumlin, Dublin in 1949. He went to primary school in Donore Avenue and to secondary school, on a scholarship, to the Marian College in Ballsbridge, Dublin. On completion of this, he worked in the commercial sector for three years to accumulate the resources to fund a degree course in UCD.  

In 1973, he graduated with a bachelor's degree in Social Science. A master's degree in Sociology in UCC followed in 1976. He went to the London School of Economics and Political Science, with the assistance of an ESRI fellowship, and graduated with a Master of Science in Sociology in 1977.

This was awarded with distinction, the highest award category that the LSE then offered. He was appointed to a lectureship in University College Cork in 1978 and to a senior lectureship in 1996. After some initial work in the sociology of development, his future teaching and research focused mainly on two areas, the sociology of deviance and the sociology of the mass media.

Crime in Ireland: A Sociological Introduction was published in 1996. A second edition is due to appear in 2018. The Sociology of Media Power: An Introduction was published in 2002 and translated into Chinese in 2004.

He has been president of the Sociological Association of Ireland, won an Arts Faculty Achievement Award in 2004, wrote a weekly column for two newspapers in Cork over a period of six years, and was an elected member of the governing body in University College Cork from 2007 to 2012 and of the National University of Ireland.

Over a period of about 15 years, he was involved in Oscail, the online university. He served for ten years as a board member of the Cork Auto Diversion Project. Along with colleagues in Law, he set up a master's degree in Criminology in UCC.

In 2005, the NUI awarded him a D. Lit based on published work. In 2011 he received an Irish Penal Symposium Award. He retired in 2012 but continues to write and research in both areas. A full list of publications is available at Academia.edu and many of these can be downloaded.