1 Centre for Forensic Linguistics, Aston University, Birmingham, England, United Kingdom; Forensic Evaluation Ltd, Birmingham, England, United Kingdom. Electronic address: geoff-morrison@forensic-evaluation.net.
2 Office of the Chief Forensic Scientist, Victoria Police Forensic Services Department, Melbourne, Victoria, Australia.
3 School of Life and Health Sciences, Aston University, Birmingham, England, United Kingdom.