IRS email tapes destroyed after the issuance of a preservation order

Fox News:

The lead government watchdog for the IRS revealed Thursday that computer evidence was erased during the investigation into the agency's targeting scandal, months after the IRS was told to preserve documents.

J. Russell George, the Treasury inspector general for tax administration, testified to the House Oversight and Government Reform Committee that IRS employees erased computer backup tapes shortly after officials discovered thousands of emails related to the tax agency's Tea Party scandal had been lost.

As many as 24,000 emails were lost because 422 backup tapes were "magnetically erased" around March 4, 2014.

George said his office found no direct evidence the tapes were destroyed to hide information from Congress or law enforcement. But the destruction nevertheless defied a preservation order, and is sure to raise suspicions over motive.
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I think the IRS has lost any presumption of good faith in the production of materials in this matter.  If the case were in a court the judge could issue an order that there is a presumption that the material in the case would not help the IRS.  In the court of public opinion that is also likely to be the result.  It raises the suggestion that the tapes were destroyed to protect someone in the administration who was behind the push to harass conservative groups.