The indictment of former president Donald Trump by Biden Justice Department special counsel Jack Smith on four felony charges arising out of his efforts to undo President Biden's victory in the 2020 election is momentous — not just in its potential impact on our politics, but in what it could mean for the rule of law.

We have on many occasions condemned Trump's appalling actions in the aftermath of the 2020 election. They were impeachable. He came close to being convicted in a Senate impeachment trial; with 57 senators finding him guilty, he was saved only by the Constitution's two-thirds supermajority mandate for conviction and disqualification.

Now, through a special counsel it appointed for this precise purpose, the Biden Justice Department is attempting to use the criminal process as a do-over for a failed impeachment. In effect, Jack Smith is endeavoring to criminalize protected political speech and flimsy legal theories — when the Supreme Court has repeatedly admonished prosecutors to refrain from creative theories to stretch penal laws to reach misconduct that Congress has not made illegal.

In our constitutional system, Congress is trusted with the duty to check egregious executive misconduct. Its failure to convict Trump understandably galls many of his opponents — left, right, and center. This feeling is accentuated by their sense both that Trump is unfit for the presidency and that there is a very real possibility that he could be elected president again.

Hence the pressure on the Justice Department to hold Trump accountable in a way the political system did not. But criminal prosecution is an inapt substitute for the congressionally driven political process that the Constitution set up to address gross abuses of power.

Public office is a privilege, not a right. That is why a president may be ousted, without all the protections of criminal due process, for violating the public trust. In contrast, criminal prosecution is designed to address private wrongs, not derelictions of public duty. It endows the accused with enhanced protections because at stake are rights — liberty, property — not the privilege of political power.

Whether misconduct rises to the level of an impeachable offense is indefinite, left to the people's representatives to assess based on what the facts and circumstances say about a public official's fitness for duty. Criminal offenses are the antithesis of that. They must be defined by statute with sufficient clarity so that the average person knows what is forbidden, and a defendant is presumed innocent. A guilty verdict must be supported by proof beyond a reasonable doubt — proof not only that the person performed the statutorily prohibited acts, but also did so knowing that his conduct was illegal.

Here, it is not even clear that Smith has alleged anything that the law forbids. The indictment relates in detail Trump's deceptions, but that doesn't mean they constitute criminal fraud. As the Supreme Court reaffirmed just a few weeks ago, fraud in federal criminal law is a scheme to swindle victims out of money or tangible property. Mendacious rhetoric in seeking to retain political office is damnable — and, again, impeachable — but it's not criminal fraud, although that is what Smith has charged. Indeed, assuming a prosecutor could prove beyond a reasonable doubt that Trump hadn't actually convinced himself that the election was stolen from him (good luck with that), hyperbole and even worse are protected political speech.

As for obstruction, Americans, presidents included, have a right to attempt to influence Congress, even based on dubious or imagined evidence. To establish obstruction, Smith must prove that Trump's efforts at persuasion were corrupt — again, in the sense that he knew his badgering and lobbying had no factual or legal merit. The concept of corruption is meant to reach clearly criminal conduct, such as evidence manipulation or witness tampering. It has never been understood to reach wrong-headed legal theories. To apply it that way, as Smith proposes, would chill not only political speech, but the constitutional right of a defendant to mount a legal defense.

Finally, Smith is charging Trump with a civil-rights violation, on the theory that he sought to counteract the votes of Americans in contested states and based on a post–Civil War statute designed to punish violent intimidation and forcible attacks against blacks attempting to exercise their right to vote. What Trump did, though reprehensible, bears no relation to what the statute covers.

In his press conference announcing the charges, Smith — for good reason — did not dwell on his questionable charges. He instead emphasized the Capitol riot. Anyone witnessing his remarks would have believed that Trump had incited a forcible attack on the Capitol. Of course, Smith has not charged him with any such thing because he doesn't have the evidence to tie him criminally to the riot. The prosecutor was making a political statement, clearly aimed at swaying the jury pool in blue Washington, D.C., where the Justice Department brags daily about having charged more than a thousand rioters.

There is a reason Smith does not have a solid statutory crime to rely on. To criminalize the conduct for which he seeks to convict Trump, Congress would have to write sweeping laws that could easily be wielded by one party against another to punish objectionable political conduct. That would undermine both electoral politics and the rule of law.

This indictment shouldn't stand.