Operation Fast and Furious/take them down

About
A memorandum from Darrell Issa on 2012-05-03 states that:

One confidential witness told Congress that he overheard Scot Thomasson, chief ATF spokesman, say early on in the congressional inquiry into Fast and Furious: “We need to get whatever dirt we can on these guys [the whistleblowers] and take them down.”

This would seem to indicate that the testimony took place in a hearing to which there were other witnesses, and possibly under oath -- but since the testimony was "confidential" and no date is given, tracking it down may be quite difficult.

Links

 * 2013-06-29
 * Issa, Grassley release details about Fast and Furious whistleblower retaliation, cover-up: cites Grassley/Issa letter, which cites but gives insufficient information for locating it
 * Fast and Furious whistleblowers now supervised by ATF manager who allegedly threatened retaliation: cites Grassley/Issa letter
 * 2013-06-30 ATF’S Fast and Furious Coverup Exposed: cites Daily Caller post