Why would the CIA destroy interview tapes?

The former intelligence official who described the decision to destroy the tapes said Mr. Rodriguez's primary concern was the safety of C.I.A. agents whose faces could be identified in the tapes. The tapes were destroyed amid growing Congressional and legal scrutiny into the C.I.A's detention and interrogation program.

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Rodriguez's concerns have been validated by the reaction of the Democrats to the knowledge the tapes were destroyed. It is clear that many Democrats would like to turn them into abu Ghraid photo ops to be passed to media hostile to the administration. Making the agents pawns in their political games would be just part of their bad faith arguments against the administration now that the fear of another horrific attack has passed. Now they will want to attack the lawyers too. I look for Democrats to make further attacks on an already weak intelligence agency and use this as an excuse to gut clandestine operations again.