As ridiculous as the House Republicans’ Benghazi committee has become , at least the GOP’s investigation is scrutinizing a real event. Sure, by Republicans’ own admission, the entire exercise is a partisan political stunt. And sure, the events in Benghazi in 2012 have already been investigated by seven other congressional committees. But at its root, four Americans died in a terrorist attack that actually happened.

The existence of the House Republicans’ anti-Planned Parenthood committee is arguably tougher to defend.

The Washington Post’s Dana Milbank highlighted the latest antics of the panel’s far-right chair, Rep. Marsha Blackburn (R-Tenn.), who “isn’t one to worry about appearances.”

The Tennessee Republican didn’t make any pretense this week of being impartial with the committee she chairs, the House Select Investigative Panel on Infant Lives, commonly known as the Planned Parenthood committee. On the eve of her panel’s Wednesday’s hearing, Blackburn went over to Georgetown University to participate in a protest against Planned Parenthood, the very entity she is supposed to be investigating…. Then Blackburn showed up at her committee hearing the next morning and proclaimed, “My hope is that both parties can work together.”

Of course, when Blackburn talks about the parties “working together,” what she’s referring to is a hope that Democrats will simply go along with a culture-war crusade as if the GOP’s latest select committee were a legitimate exercise, probing a genuine controversy.

It is not. As we’ve discussed before, the “controversy” surrounding Planned Parenthood and fetal-tissue research effectively came to an end months ago. Despite the far-right uproar surrounding “undercover” videos targeting the health organization, a Texas grand jury cleared Planned Parenthood of any wrongdoing , and instead indicted the conservatives responsible for the “sting” operation against the group.

This followed word from 12 states, which had launched official investigations into Planned Parenthood’s work, and each of which reached the same conclusion : the organization did not illegally sell fetal tissue.

These facts prompted the editorial board of the Washington Post to argue that it’s time for the GOP to “give up its crusade” against Planned Parenthood. As yesterday’s hearing reminded us, congressional Republicans have instead decided to ramp up the witch hunt.

MSNBC’s Irin Carmon was also there for yesterday’s hearing, and took note of who wasn’t in the room.

The work of David Daleiden, an anti-abortion activist currently facing criminal indictment in Texas whose home was recently searched by California authorities, had sparked the committee’s creation. But he was not called to testify about his secretly recorded videos of abortion providers, for which he posed as a procurer of fetal tissue for medical research. (Daleiden did, however, live tweet the proceedings.) Also absent were representatives of StemExpress, the actual fetal tissue procurement company that is in the crosshairs of the committee, though according to ranking minority member Democratic Rep. Jan Schakowsky, the company’s procurement director offered to explain its cost structure to the committee. “The Chair ignored that offer and, instead, called this public hearing and invited witnesses who have no firsthand knowledge of the facts to opine about potential criminal misconduct,” Schakowsky said.

There’s a reason Democratic members of the committee described the proceedings as a “farce,” a “kangaroo court” and “a witch hunt.”

The apparent purpose of yesterday’s hearing was “proof” of a clinic making profit on fetal-tissue donations. As the Washington Post’s piece added , the evidence was about as credible as the hearing itself.

[T]his incendiary “exhibit” – asserting that any abortion clinic that receives any payment for fetal tissue is breaking the law – turned out to be not evidence but an undocumented claim by the Republican staff. “I think that these exhibits were created from whole cloth,” said Rep. Diana DeGette (D-Colo.) a member of the panel. She objected to the use of the exhibits, claiming they violated House rules. Republicans moved to table her objection and prevailed on a party-line vote. Rep. Jerry Nadler (D-N.Y.) tried again. He raised a parliamentary inquiry about how the “pure profit” conclusion was reached – particularly because it was contradicted by three other exhibits that appeared to document activities performed by abortion clinics in the tissue sales that have associated costs.

Committee Republicans not only didn’t care, they also based much of yesterday’s discussion around materials no one could substantiate.

If there’s a credible defense for such a reckless waste of Congress’ time, it’s hiding well.