You are absolutely correct, Ron. Just about anything that's on or has been on an electronic storage medium that has not been physically destroyed can be "mined" with the proper equipment and knowledgable individuals. A reasonal approach to requesting access to such information is understandable (except, perhaps, in the case where such forewarning might be expected to result in destruction of evidence).
Again though, the person who has nothing to hide has nothing to fear.
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" In walks the village idiot and his face is all aglow; he's been up all night listening to Mohammad's radio" W. Zevon