The Constitution is the supreme law of the land, thus, all government behavior must conform to it. It is, of course, notwithstanding its supremacy, an imperfect document. Its original iteration in 1789 -- and even after the addition of the Bill of Rights in 1791 -- implicitly recognized slavery, permitted the states to limit voters to adult white landowning men and did not require the states to protect personal liberty.

Under the Constitution, impeachment -- a charge accusing a present or former federal officeholder of paramount wrongdoing -- can only be had if the charge is for a criminal act. The constitutional language -- "treason, bribery, or other high crimes and misdemeanors" -- means the criminal act must be grave and strike at the security of the republic.

President Andrew Johnson was impeached in 1868 for firing his secretary of war, in defiance of a statute -- which was no doubt unconstitutional -- prohibiting him from doing so. Whatever he did, it was not criminal, nor was it the type of behavior that affected the security of the republic. He was a southerner who was despised by the Radical Republicans who ran the government after Lincoln’s death. He was acquitted in the Senate by one vote.

President Bill Clinton was impeached in 1998 for lying under oath about a private consensual sexual relationship. There was a crime -- perjury -- but it was not of the species of crime that the framers contemplated when they wrote "other high crimes and misdemeanors." It surely lacked the gravity of treason and bribery.

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Clinton was despised by the Republicans who ran the House. Either they believed his presidential perjury about consensual sex was a serious threat to the republic or they used it as an instrument to embarrass him. He was acquitted in the Senate.

Both of President Donald Trump’s impeachments were based on presidential behavior that either sought to use the instruments of government for personal gain (his 2019 impeachment was based on favors he requested from the president of Ukraine in return for military aid) or threatened to interrupt the constitutional duties of the Congress to prevent it from certifying the results of the 2020 presidential election. He, too, has been despised by the Democrats that have run the House, and they looked for and found mechanisms to tarnish his legacy.

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Add to this the unique -- though not unprecedented -- feature of Trump’s second impeachment trial: It occurred while he was a private citizen. He was acquitted both times in the Senate.

The point of this brief presidential impeachment history is that the Constitution is flexible and gives opportunities for congressional mischief.

This is particularly so in the cases of impeachment. The House of Representatives and the Senate write their own rules and procedures -- for impeachment and for all else. The procedures once enacted are not subject to challenge in the other house or in the courts.

Congress’ internal workings -- though biased, unfair and even bullying -- are only subject to appeal to the voters at the next election.

Impeachment is far more a political mechanism than a legal one. In Johnson’s case, there were no hearings and there was next to no debate in the House before the vote to impeach.

In Trump’s recent impeachment, he was denied due process as well, since there were no House hearings. In Clinton’s case and Trump’s first case, there were extensive due process hearings at which evidence was developed and challenged, and both presidents were represented by counsel.

Was Trump’s second impeachment fair? By the standards of due process to which we are accustomed, and which the courts require in civil and criminal cases, it was not. Yet, by the history of impeachments and the political flexibility that the Constitution admits, it followed the rules set forth by each of the two houses.

To my trained legal ears, the use of hearsay ("someone told me what he heard"), rather than eyewitness testimony, is anathema. And under the natural law that protects all speech, the idea of punishing someone for speech is anathema.

The First Amendment’s iconic language that "Congress shall make no law ... abridging the freedom of speech," and the natural primacy of free speech in our history and culture, and the Supreme Court’s famous Brandenburg case collectively mean that every conceivable lawful interpretation of the speech under scrutiny must first be factually excluded before a person can be tried by the government in any venue on account of what he said.

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The evidence I saw the House managers offer showed that Trump morally encouraged the mob, was indifferent to its destruction and did little to stop the violence. Yet, the words I heard him utter were and remain protected speech. He used satire, hyperbole and exaggeration -- each of which is protected.

Protected speech cannot constitutionally form the basis of any legal action against anyone. Unless, of course, you get to write the rules, as the House and Senate do.

Where does all this leave us? It leaves us where we began. The Constitution is the supreme law of the land. It recognizes that we have natural rights that cannot be interfered with by the government absent due process. But its vitality as a guarantor of liberty is only as durable and reliable as is the fidelity to it of those in whose hands we have reposed it for safekeeping.

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Is the Constitution in good hands? It is not. In defiance of the Constitution, its keepers permit political prosecutions, suppressions of speech, thefts of liberty, invasions of privacy and the slaughter of innocents in the womb.

These are perilous times. Our freedoms are hanging by a thread -- a thread that its keepers keep weakening.

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