Attorneys for the IRS have told a federal court that they have not searched various “other sources” for the missing emails of former agency official Lois Lerner, claiming that doing so would be fruitless.

The attorneys made the assertions in a court filing last month as part of a Freedom of Information Act lawsuit over the missing emails that was filed by the conservative watchdog group Judicial Watch. The IRS has said that potentially thousands of emails belonging to Lerner, a central figure in the agency’s targeting of conservative groups, were lost in a hard drive crash in 2011.

Judicial Watch has asserted that the IRS could recover the missing emails by various alternative means, such as searching the agency’s disaster recovery tapes, searching agency servers and searching a “government-wide backup system”

In response, the IRS said that it did not search the agency’s servers for the emails because it determined doing so “would not result in the recovery of any information.” In addition, the IRS said did not search the agency’s disaster recovery tapes because the tapes are reused or destroyed every six months, therefore rendering them useless in the hunt for Lerner’s emails from or before 2011.

In response to Judicial Watch’s claims that the emails should be available on a “government-wide backup system,” the agency argued that no such system exists.

The IRS said it had not submitted to the court declarations about “any of the foregoing items because it had no reason to believe that they were sources from which to recover information lost as a result of Lerner’s hard drive failure.”

Judicial Watch said in a statement Wednesday that its attorneys have determined that the IRS "did not undertake any significant efforts to obtain the emails."

“The Obama IRS couldn’t care less about the federal court’s orders to provide full information about the ‘missing’ Lois Lerner emails,” Judicial Watch President Tom Fitton said in a statement. “Instead, the IRS, with the help of a compromised Justice Department, has engaged in a series of transparently evasive distractions.”

However, the IRS argued it is doing everything required to comply with the lawsuit.

“As the IRS has said before, it continues to cooperate with the investigations and legal actions underway,” the agency told Fox News. “Suggestions to the contrary are inaccurate and misleading. Beyond this, as this matter is in litigation, the IRS defers to its court filings.”

In previous court declarations, IRS technology officials have insisted they did everything they could to fix and recover data from the hard drive of Lerner. However, they said their efforts were fruitless, and some of Lerner's emails were lost.

Lerner, who has since retired, headed the IRS unit that reviews applications for tax-exempt status, when applications from Tea Party groups and other conservative organizations were held up for extra scrutiny.

The Associated Press contributed to this report.