DeCillia attended journalism school at the University of Regina after getting an honours degree in international studies from the University of Saskatchewan, during his last year at the University of Saskatchewan he also helmed the student newspaper "The Sheaf."
DeCillia studied politics and communication at the London School of Economics as a Chevening Scholar. His dissertation about the mainstream media’s coverage of Canada’s military mission in Afghanistan won the Silverstone Prize.
DeCillia has covered stories in south Asia, Europe and across North America. He was embedded with Canadian forces Kandahar in Afghanistan in 2006 and 2007.
DeCillia runs marathons. He has a wife and son.
- "Chevening Alumni - Scholarships - Education - British Council - Canada". British Council. Retrieved 2011-03-07.
- "Electronic MSc Dissertation Series - Working Papers - Research - Department of Media and Communications - Home". .lse.ac.uk. 2011-02-26. Retrieved 2011-03-07.
- "Program Guide - Personalities". CBC.ca. Retrieved 2011-03-07.