The revelation last week by Minnesota state Sen. Scott Dibble that he has been the victim of revenge porn by a man with whom he formerly had an extramarital affair was stunning ("Senator: I'm revenge porn victim," Nov. 2).

The chastened DFL legislator from south Minneapolis, who is nearing two decades in the Senate, termed the dissolved relationship as a "brief, intimate and consensual" one. Colleagues on both sides of the aisle expressed support, and other empathetic reactions came from the public.

Dibble's disclosure received an extraordinary amount of attention because it came on the heels of the fiery resignation from Congress by Katie Hill, a freshman Democratic member of the House from California. She left her hard-won seat in a Republican-leaning district after she became the subject of publication of her affair with a campaign staffer accompanied by nude photographs of her on social media orchestrated by her estranged husband.

The two incidents highlight the phenomenon of revenge porn, a rapidly evolving method of using the internet and social media to strike back at an individual, usually due to fallout from a marriage or other romantic relationship. While these two matters reflect its use in the political arena, it also takes place in other contexts, such as employment and workplace arrangements.

Although there is no federal law addressing the topic, Minnesota is one of 33 states that have laws that prohibit the practice. The Minnesota measure, enacted in 2016, makes it a gross misdemeanor, punishable by up to a year in jail and $1,000 fine, to knowingly disseminate, publish or sell explicit sexual images of an individual without the subject's consent. Depending upon the scope of the distribution, pecuniary gain or prior offenses, the offense can be treated as a felony punishable with up to three years imprisonment.

The law, grandiosely titled "Nonconsensual Dissemination of Private Sexual Images," is a manifestation of public revulsion of the practice of reprisal porn. But it looks — and sounds — a lot more potent than it actually is. It is rarely invoked, impractical to enforce and might not even be valid.

The Hill and Dibble incidents reflect the inefficacy of this type of legislation. In Hill's case, without a federal law that could come to her aid, she could seek refuge under any applicable laws in California or elsewhere where the claimed offenses occurred. As for Dibble, the alleged wrongdoer reportedly lives abroad and, thus, is outside the reach of the state statute.

Even if these cases could be prosecuted, they might not be pursued. Victims of revenge porn will often not want to initiate a criminal proceeding for fear that it would expose, no pun intended, the salacious images they seek to suppress. Many revenge-porn targets, particularly celebrities or other well-known personalities, are understandably reluctant to place themselves and their images in the public domain, along with the often-sordid tales that accompany them.

Overcoming these obstacles, however, runs into another one: The law may not be constitutional. Imposition of criminal sanctions for communicating images, even lewd ones without consent of the subjects, could be subject to meritorious challenge as a violation of the right of freedom of expression under the First Amendment of the U.S. Constitution or its counterpart under the Minnesota Constitution.

A defense on constitutional grounds would draw upon ample precedent of the U.S. Supreme Court, which has in the era of Chief Justice John Roberts consistently construed the freedom-of-speech clause quite broadly, even to the point of drawing an objection by members of the liberal wing of the tribunal that the conservative majority has "weaponized the First Amendment," allowing it to be used to permit objectionable antisocial behavior under the guise of free speech.

The phrase was coined last year by Justice Elena Kagan, who incidentally spoke at a well-attended symposium sponsored by the University of Minnesota Law School a couple of weeks ago.

The pattern is reflected in a pair of cases decided within the past decade. In one of them, a lawsuit called Snyder v. Phelps, the justices in 2011 overturned a lower-court jury verdict of nearly $11 million for a family that suffered huge emotional distress due to picketing accompanied by hateful protests by an extremist anti-gay-rights group at their son's military funeral. The court deemed the protesters to be protected by the First Amendment, notwithstanding the vile nature of their behavior.

The previous year, the high court in United States v. Stevens reversed a criminal conviction of a Pennsylvania man who was charged with violating the Federal Decency Act (there's another catchy moniker), which proscribed commercial making, distributing or selling of depictions of animal cruelty. His offense consisted of selling foreign-made "snuff" videos of animal decapitations and other depravities. While not condoning the abhorrent behavior, the jurists similarly found the measure an unconstitutional restraint of free speech.

Both decisions were nearly unanimous, with only one dissenter, Justice Samuel Alito, in each of them. They both were authored by Chief Justice Roberts, who happened to be the University of Minnesota Law School symposium guest speaker last year.

But one need not go beyond the East Side of St. Paul to encounter similar judicial reasoning. The 1992 case of R.A.V. v. City of St. Paul struck down a municipal "hate" measure in that city that was used to prosecute a juvenile who participated in an intimidating cross-burning on the lawn of an African-American family that had recently moved into the neighborhood. The high court set aside a ruling of the Minnesota Supreme Court that validated the measure. The unanimous ruling, written by Justice Antonio Scalia, deemed the measure a constitutionally impermissible restriction on the expressive content of the hateful behavior.

These rulings giving lenity to conduct that has an expressive component are distinct from other cases in which the courts, including those in Minnesota, have upheld sanctions against those who engage in behavior that is actually intimidating or threatening. In those matters, arousing fear or creating jeopardy to personal or physical safety consistently has resulted in adverse rulings to the wrongdoers. But the Minnesota revenge-porn statute does not depend upon intimidation or threatening behavior; it purports to criminalize the mere dissemination of the imagery regardless of the actual intent of the distributor or, more importantly, the effect on the subject.

In the absence of evil intent or actual harm, the U.S. Supreme Court's jurisprudence establishes the framework for a potentially successful challenge to the Minnesota revenge-porn statute and others of similar ilk elsewhere. The prospective invalidity of the statute in a criminal case would not leave victims without recourse. They could still pursue lawsuits against the wrongdoer on various grounds, including invasion of privacy, infliction of emotional distress, and possibly defamation, among other claims.

The fragility of the revenge-porn law is not a condonation of the repulsive behavior that it condemns. But the possibility that the measure could not withstand constitutional challenge is a recognition of the price society pays for allowing bad behavior in order to protect good conduct.

As Supreme Court Justice Felix Frankfurter once observed: "It is a fair summary of history to say that the safeguards of liberty have been forged in controversies involving not very nice people."

Marshall H. Tanick is a Twin Cities constitutional law attorney and historian.