A federal judge is demanding the Internal Revenue Service detail how former IRS official Lois Lerner's emails went missing.
U.S. District Judge Emmet G. Sullivan said he wants that explanation in writing.
Sullivan issued the order Thursday as part of a Freedom of Information Act lawsuit filed by the conservative watchdog group Judicial Watch.
Lerner is a key part of the investigation into the tax agency's targeting of Tea Party and other conservative groups.
The IRS claims it lost the emails after Lerner's computer crashed in 2011. At the time, Lerner led the IRS office that was responsible for processing requests for tax-exempt status.
The tax agency has until Aug.10 to detail how the emails went missing as well as methods for recovering them.