Something on the x-ray is either unclear or resembles a weapon: ask permission to search the bag.
Someone beeps when they walk through the magnetometer. Ask the person to be wanded.
The wand indicates a metal object in a place where metal is not usually found. Ask the person for permission to pat them down.
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by anonplz:
Give me an example of a typical case when you think there is probable cause, i.e., what are the questions which need to be answered affirmatively before the TSA can argue successfully that they have "probable cause" to search?</font>
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