Set aside the offensive theatrics from Republicans, Democrats, and witness Corey Lewandowski during the House Judiciary Committee’s impeachment-related hearing today. All sides took what should have been a serious hearing and turned it into a farce that trampled on the public’s legitimate interests.

Instead, focus on a White House offense not against mere decorum, but against bedrock principles of American government.

In informing Lewandowski, a former top campaign aide to President Trump, that his Oval Office discussions with the president should remain secret due to “executive privilege,” the White House makes a mockery of the separation of powers and the public’s right to know. If a Democratic administration had tried to enforce such a claim, Republicans in Congress would have cried bloody murder.

And the Republicans would have been right. Today’s Republicans, though, acting as if they are defense attorneys rather than independent members of Congress with duties to the broader public weal, did nothing but provide diversionary cover for both Lewandowski and the president. Their behavior was shameful.

In layman’s language, here’s the key thing to remember: So-called “executive privilege” is a real but limited exemption from rules otherwise pertaining to government transparency and congressional inquiry. The privilege is not explicitly present in the Constitution. Its extent, based on logical derivations by second-degree inference, has been expressly limited again and again by federal courts in the past 45 years. A thorough and neutral online summation of the privilege summarizes the court ruling most relevant to Lewandowski:

To be protected by executive privilege, “the subject communication must be authored or ‘solicited and received’ by the president or a close White House adviser. The adviser must be in ‘operational proximity’ to the president, which effectively limits coverage of the privilege to the administrative boundaries of the Executive Office of the President and the White House.”

Here’s the rub: Lewandowski never was on the White House staff. He was and is no more in the ambit of the “administrative boundaries of the Executive Office” than he is under the protections of Obi Wan Kenobi.

The assertion of privilege here is ludicrous. Congress rightfully enjoys oversight privilege over the conduct of the executive branch. It also has the power of impeachment to punish presidential misconduct and the lawful authority to conduct investigations related to impeachment.

According to special counsel Robert Mueller’s report, the president of the United States asked Lewandowski, a private citizen, to carry a message to attorney general Jeff Sessions to ask Sessions, in effect, to put a public thumb on the scale, in Trump’s favor, with regard to Mueller’s investigation.

If Lewandowski followed up on that directive from Trump, it is clearly arguable — maybe not definitive, but well within reason to suggest — that the directive could have been seen as part of a pattern of obstruction of justice. Even if the House inquiry right now is seen as an ill-motivated political hit job, the questions that House Democrats want to ask Lewandowski about this incident are well within the legitimate range of their committee powers of inquiry and oversight.

The White House has no legal right to silence Lewandowski on that question, especially in such circumstances. Lewandowski is a material witness. He was not a White House employee. He is asserting, and can assert, no Fifth Amendment privilege, because there is no suggestion that he himself broke any law. He is under duly issued congressional subpoena. Therefore, he must answer Congress’ questions. Period.