The claim isn't entirely unfounded. According to the Ministry of Defence , facial hair must be entirely shaven in order to comply with the strict Army Dress Regulations. However, there are plenty of exceptions to the listed dress code — like religion, for example. In fact, the document reads: "[Moustaches] are to be trimmed and not below the line of the lower lip. Beards and whiskers may be worn only with authority, and this will usually be granted only on medical or religious grounds, or where tradition permits."