The IRS told congressional investigators on Friday that it has lost about two years’ worth of emails to and from Lois Lerner, a central figure in the agency’s scandal over improper scrutinization of applications for tax-exempt status by Tea Party and other conservative groups. The agency says that because Lerner’s computer crashed in 2011, they cannot locate many of her emails prior to that year. “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,” said Rep. Dave Camp (R-MI), chairman of the House Ways and Means Committee (one of three congressional committees investigating the IRS’s handling of Tea Party applications. ”There needs to be an immediate investigation and forensic audit by Department of Justice as well as the inspector general.”