(NBC News) The investigation into whether the IRS deliberately targeting conservative groups has taken a bit of a left turn, and now lawmakers want to special prosecutor to look into why some of the evidence disappeared.
Two years worth of emails that Congress wants to see have been destroyed and some Republicans think that was no accident.
"You possibly have people at the IRS who are committing crimes and they're not being held accountable," declared Rep. Mike Turner, R-Ohio.
The emails were to and from Lois Lerner, the now retired IRS employee who headed the office that determines whether groups seeking tax exempt status are too political.
Some conservative groups faced extra scrutiny.
Lawmakers believe the emails could explain why, but the IRS chief tells Congress he first learned in April that Lerner's hard drive was destroyed after her computer crashed, and backup tapes were recycled.
The IRS blames Congressional budget cuts.
"It is not unusual for computers anywhere to fail especially at the IRS in light of the aged equipment IRS employees often have to use," said IRS Commissioner John Koskinen.
Democrats defended the IRS, noting tens of thousands of emails that were submitted.
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