With new technology came a new type of Washington scandal: missing emails.

In the latest instance, the vanished emails belonged to Lois Lerner, former head of the exempt organizations division at IRS. She's the official who oversaw the scrutiny of applicants for tax-exempt status as 501(c)(4) social welfare groups — a process that conservatives allege was meant to block Tea Party groups.

The controversy blew up just over a year ago. Lerner was pushed out of the IRS; the House cited her for contempt of Congress.

Congressional investigators demanded to see her emails, but the IRS can't seem to find them all. Here's the short version of what the agency told Congress on Friday:

Lerner's computer hard drive crashed in mid-2011. She asked IT to revive it, but it couldn't.

The IRS uses Microsoft Outlook for its email. Policy at the time was to back up emails for six months, then wipe and reuse the tapes (they're now preserved, not recycled). The IRS limited employees to roughly 1,800 emails in their inboxes (the cap has been raised). Employees could move old emails to their computer hard drives. They're required to print and file any "official records" of public business.

You can see where this is going. The agency says Lerner's emails fell into a bureaucratic black hole, first routinely erased from the backup tapes and then, months later, obliterated in the crash.

The IRS says it tried to work around the loss, searching the computers of 82 IRS officials for emails carrying Lerner's name as sender or a recipient. But that would miss any email correspondence outside the agency.

In any case, the IRS says Congress has gotten or will get some 67,000 emails either from or to Lois Lerner.

Republicans on Capitol Hill want to know why the agency didn't say anything sooner. And they, like the conservative blogosphere, don't buy the story.

"Isn't it convenient" is how Republican Rep. Darrell Issa, chair of the House Oversight Committee, put it. "If there wasn't nefarious conduct that went much higher than Lois Lerner in the IRS targeting scandal, why are they playing these games?"

Ways and Means Committee Chairman Dave Camp and Oversight subcommittee Chairman Charles Boustany said, "We are simply not going to accept the IRS claim that these documents are not recoverable." They've scheduled IRS Commissioner John Koskinen to testify next Tuesday.

Democrats and liberal bloggers didn't have much to say.

If this saga seems familiar, maybe you're remembering the 2007 case of emails missing in the George W. Bush administration. Then, Senate Judiciary Committee Chairman Patrick Leahy, a Democrat, said, "It's like saying the dog ate my homework."

You might even recall the Clinton administration's disappearing emails of 2000, which were thought to involve, among other scandals, the presidential infidelity and profligate Democratic fundraising.

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