More evidence that Eric Holder is covering up the IRS scandal?

What possible reasonable justification could the Obama administration have for not providing contact information for a former employee?  From Fox News:

A top House Republican is demanding the Department of Justice hand over contact information on a former employee accused of having a conflict of interest in the IRS targeting scandal investigation.
In a Sept. 3 letter, Rep. Jim Jordan, R-Ohio, once again asked Attorney General Eric Holder for information on Andrew Strelka’s whereabouts.
“Despite notifying [Oversight and Government Reform] Committee staff that the [Justice] Department no longer employs Mr. Strelka, the department has refused to assist the committee in speaking to Mr. Strelka directly,” Jordan wrote. “The department’s efforts to prevent the committee from learning Mr. Strelka’s whereabouts suggest the department has cause for keeping him from speaking with the committee.”
Jordan says he wants Strelka’s contact information so the Oversight Committee can conduct a transcribed interview. The letter gives Holder a Friday deadline for the information. . . .