Since gaining a Bachelor of Science Degree in Applied Chemistry Terrence J Napier has worked as a Forensic Scientist. He was employed by the Metropolitan Police Forensic Science Laboratory for over 8 years in traces and marks examinations but specialized in the recovery, visualization and comparison of marks.

He then joined the West Yorkshire Police as a Forensic Science Manager, where he spent 6 years working almost exclusively on the examination of footwear marks but regularly advised and trained officers in the significance of non biological contact trace evidence including glass.

Terrence J Napier now works as an independent Forensic Scientist.