Although not really forensic linguistics this got me thinking about reliability and expertise in lip-reading evidence. A quick trawl of the Internet came up with this interesting and critical paper:
Although this report is rather old and the criticisms may no longer be current it is noticable that this practitioner is reported to be working in a current case in Australia:
As with lip-reading evidence forensic linguistics has no formal qualification requirements and no authoritative system of accreditation. It is also quite possible that a practitioner could continue in their work after significant criticism or censure by a Court.
Via Tim Grant