Updated

The House of Representatives will vote in May on whether to hold former IRS official Lois Lerner in contempt for her role in the agency's targeting of conservative groups, according to a memo released Friday by House Republicans.

The memo from House Majority Leader Eric Cantor, R-Va., said the contempt vote would proceed unless Lerner agrees to testify before the House Oversight and Government Reform Committee about the targeting scandal.

“Thorough investigations by the Oversight and Government Reform Committee as well as the Ways and Means Committee have revealed findings that indicate that Ms. Lerner played a central role in the illegal targeting of conservative groups by the IRS,” the memo reads.

Last May, Lerner refused to answer questions at a hearing about IRS agents singling out tea party applications for extra scrutiny. She again refused to answer questions in March, citing her Fifth Amendment right against self-incrimination.

The Oversight Committee voted earlier this month to hold her in contempt. All Republicans voted in favor and all Democrats voted against.

House Republicans on Thursday stepped up their investigation into the Justice Department's possible role in the targeting scandal, citing an email that purportedly suggests high-level DOJ officials may have been involved.

Emails published last week showed correspondence between Lerner and others at the IRS regarding the Justice Department's interest in investigating "political" groups.

In a May 2013 email obtained by Judicial Watch, Lerner responded to an inquiry from Richard Pilger, director of the DOJ's election crimes branch, about whether tax-exempt groups could be criminally prosecuted for lying about political activity.

Rep. Darrell Issa, R., Calif., chairman of the Oversight Committee, said Thursday that a previously undisclosed email indicates that Pilger did not reach out to Lerner on his own.

Pilger noted in an email to Lerner on May 8th 2013, “I have been asked to run something by you," according to a news release from Issa's office. The email reportedly does not indicate who had asked Pilfer to contact Lerner, who disclosed the targeting scandal just days later.

Issa and 16 other Republican lawmakers are asking Attorney General Eric Holder to produce documents and to make Pilger available for an interview.

“Mr. Pilger’s communications with Ms. Lerner are also striking for their timing. They show that the IRS and the Justice Department were actively considering efforts to target tax-exempt organizations just two days before Ms. Lerner’s public apology for the targeting," the lawmakers wrote.

Senior Justice Department officials told Fox News last week that the accusations surrounding the emails are "conflating two separate issues."

They said the phone call between Lerner and Pilger was in reference to a question posed during a Senate committee hearing in April 2013 by Sen. Sheldon Whitehouse, D-R.I., who was asking about groups who already enjoyed tax-exempt status but in his estimation may have been lying when they said they did not engage in political activities.

DOJ officials also point out that Pilger is, and was not, running the IRS investigation, and that the call or follow-up emails did not lead to any follow-up investigation of any of the groups Whitehouse was asking about.

The Obama administration at the highest level denied the targeting, from 2010 through the 2012 presidential election cycle, was illegal or politically motivated.

President Obama told Fox News in February there was “not even a smidgen of corruption” in connection with the targeting.