AP
Lois Lerner
The IRS' claim sparked outrage from congressional investigators still probing the targeting, and it could reignite another controversy for the Obama administration.
The House Ways and Means Committee released a statement Friday saying the IRS had informed the committee it had lost some of Lerner's emails from January 2009 through April 2011 because of a computer crash.
According to the House committee, the IRS said it can only produce Lerner's emails she sent to and received from IRS employees. The IRS said it does not have emails Lerner sent to and received from other outside agencies - "such as the White House, Treasury, Department of Justice, FEC, or Democrat offices," the House committee said.
"The fact that I am just learning about this, over a year into the investigation, is completely unacceptable and now calls into question the credibility of the IRS's response to Congressional inquiries," House Ways and Means Committee Chair Dave Camp (R-Michigan) said in a statement.
Lerner headed the IRS division that processed applications for tax-exempt status. The agency caused a fury last year when it admitted it had targeted certain conservative and Tea Party-aligned groups for extra scrutiny when examining their applications. But so far, investigators have not found any evidence that anyone outside the IRS was aware of the targeting or was involved in carrying it out.
Lerner was the official who first admitted the agency's conduct while answering a planted question during a conference. She left the IRS last year amid the resulting firestorm but has refused to testify, invoking her constitutional right against self-incrimination multiple times when subpoenaed before congressional hearings. In May, she was held in contempt of Congress.
House Oversight Committee Chair Darrell Issa, whose committee has led the IRS investigation, accused the IRS of "playing games."
"Isn't it convenient for the Obama Administration that the IRS now says it has suddenly realized it lost Lois Lerner's emails requested by Congress and promised by Commissioner John Koskinen?" Issa said. "Do they really expect the American people to believe that, after having withheld these emails for a year, they're just now realizing the most critical time period is missing?"
For its part, the IRS said it was able to recover about 24,000 pieces of correspondence among Lerner and other IRS employees by finding email chains on which she was copied. The IRS said it is producing 67,000 emails written by and to Lerner between 2009 and 2013.
"The IRS has remained focused on being thorough and responding as quickly as possible to the wide-ranging requests from Congress while taking steps to protect underlying taxpayer information," the agency said in a statement.