The House Republicans’ Benghazi Committee not only still exists – today is its 722nd day – it also continues to make demands of the Pentagon. As of yesterday, I’m starting to get the sense that the Defense Department is getting a little tired of the GOP’s panel’s requests.

Committee Democrats issued a document this morning that’s worth paying attention to.

Today, Rep. Elijah E. Cummings, the Ranking Member of the House Select Committee on Benghazi, Rep. Adam Smith, the Ranking Member of the House Armed Services Committee, and Rep. Adam Schiff, the Ranking Member of the House Permanent Select Committee on Intelligence, released a letter from the Assistant Secretary of Defense to Select Committee Chairman Trey Gowdy exposing the latest abuses by Select Committee Republicans.

The three-page letter, which is available in its entirety online (pdf), is from Assistant Secretary of Defense Stephen C. Hedger, and was sent to Benghazi Committee Chairman Trey Gowdy (R-S.C.) yesterday. In it, Hedger goes into quite a bit of detail noting the extent to which the Pentagon has already cooperated with the panel’s request for materials and information, but the letter also suggests Gowdy and his Republican colleagues are … what’s the phrase I’m looking for … pushing their luck.

“The Committee has made requests of individuals who seem unnecessary even for a comprehensive investigation,” Hedger wrote, “or has insisted we prioritize certain requests only to later abandon the request.”

In one case, Benghazi Committee Republicans told the Pentagon to track down four pilots who weren’t deployed to Benghazi in September 2012. The Committee had already heard from their commander, but Republicans told Defense officials to track down these pilots anyway. The Pentagon obliged, eventually locating the pilots, before the committee changed it’s mind and canceled the request.

In another case, Benghazi Committee Republicans said some guy claimed on his Facebook page to be a mechanic at an air base, so the panel requested the Pentagon track him down, too. The department determined he had no relevant information.

In yet another case, Benghazi Committee Republicans said some guy called into a conservative radio show, claiming to be a pilot camera operator who saw some secret Benghazi video. The panel urged the Pentagon to find him, and after a search, no such person turned up.

All of these searches, Hedger explained, take a great deal of time, energy, and resources – for no apparent reason. His letter added:

“Finally, the DoD interviewees have been asked repeatedly to speculate or engage in discussing on the record hypotheticals posed by Committee Members and staff, regardless of their interviewee’s actual knowledge or expertise to provide appropriate analysis or insight. This type of questioning poses the risk that your final report may be based on speculation rather than a fact-based analysis or what a military officer did do or could have done given his or her knowledge at the time of the attacks. I would respectfully request that you ensure pending interviews remain focused on obtaining facts rather than encouraging speculation.”

Ouch.

Republicans have already admitted the panel is a partisan exercise, making it that much more difficult to justify its prolonged existence – at a cost of nearly $7 million . Now there’s evidence the committee is annoying the Department of Defense for reasons no one seems to understand.

To reiterate a recent observation, though I find the Republicans’ Benghazi Committee ridiculous, I’m not suggesting the deadly terrorist attack in Libya, which left four Americans dead, is unworthy of investigation. Just the opposite is true – Congress had a responsibility to determine what happened and take steps to prevent similar attacks in the future.

But therein lies the point: seven separate congressional committees investigated the Benghazi attack before the Select Committee was even created. This was already one of the most scrutinized events in American history. Republican lawmakers, however, didn’t quite care for what the evidence told them, so they effectively concluded, “Maybe an eighth committee will tell us something the other seven committees didn’t.”

Unable to substantiate various conspiracy theories, the committee is now pressing the Pentagon to find people who’ve made odd claims on Facebook and talk radio.