Your airline should have it's own Aviation Security Programme in which will be defined your security principles and procedures. But, the basis of this is the UK's National Aviation Security Programme, usually know as NASP and also the Aviation Security Act 1982 and a few others. The airline's responsibilty to ensure the safety of its passengers are defined in these documents- and you will find the answer to your question in the above.
However, the reason bags MUST be off loaded for a no-show passenger is blindingly obvious given the security threats aviation faces; but with respect to the specific rules covering this- you'll also discover that there is a specifically defined procedure covering the carraige of unaccompanied baggage which would have to met before a bag can be loaded and travel without the passenger being on board. This requirement alone, would lead to an offload of the bags of a no-show. Usually, additional screening, x-ray and or hand searchs are required for an unaccompanied bag and they must be manifested as such.
The bottom line is that the bags of a no-show passenger must always be offloaded before departure- no exceptions- ever!
Last edited by no sig; 10th Oct 2008 at 18:11.