next look closely at the Arthur Andersen case language:
REHNQUIST:
“Document retention policies,” which are created in part to keep certain information from getting into the hands of others, including the Government, are common in business. See generally Chase, To Shred or Not to Shred:Document Retention Policies and Federal Obstruction of Justice Statutes, 8 Ford. J. Corp. & Fin. L. 721 (2003). It is, of course, not wrongful for a manager to instruct his employees to comply with a valid document retention policy under ordinary circumstances.
pp 7-8
Bear in mind that the case IS NOT a precedent for ours, but it validates the propriety of destroying docs pursuant to "a valid document retention policy under ordinary circumstances."