Soviet dictators had two favorite tools for neutralizing critics and political opponents. Such people were either simply labeled criminal or mentally ill, which disqualified the opponents’ opinions and justified their confinement.

There was no need to consider the questions they raised and thus lend them stature, and there was no shortage of judges willing to find opponents guilty of something and no shortage of psychiatrists willing to diagnose disorders requiring treatment in locked hospitals. Moreover, the prospect of likely confinement dramatically reduced the number of unwelcome opinions. And thus was born the old Soviet joke: “I have an opinion, but I don’t agree with it.”

These abuses of law and psychiatry are not the problem we have today in the United States, but they are nonetheless why I find it disquieting to see Republican Senators Charles Grassley and Lindsey Graham call for a criminal investigation of Christopher Steele, the man who was hired to do traditional political opposition research and became the first to draw attention to the possibility of foreign interference in our presidential election.

These two leading members of the Senate Judiciary Committee sent a criminal referral to the Justice Department regarding Christopher Steele suggesting that he may have lied to the FBI. That would be a crime—as George Papadopolous and Michael Flynn can attest.

But there’s a difference. We know what Papadopolous and Flynn lied about. We do not know what Steele might have lied about. The problem seems to be that he had off-the-record conversations with reporters, and he may have confused dates. If that were a criminal offense Washington jails would be full of government officials of all types and both parties.

Whatever the subject of the supposed lie, the matter was already known to the Justice Department because the senators received that information, according to reports, from the FBI and DOJ which had already decided there were no grounds for prosecution. The criminal referral based on classified material raised the impression that their request was political.

Grassley’s failure to consult his Democratic counterpart on the committee contributed to the appearance of a political motive. The ranking Democrat, Senator Dianne Feinstein, angrily said she was not consulted and considered it “another effort to deflect attention from what should be the committee’s top priority: determining whether there was collusion between the Trump campaign and Russia to influence the election and whether there was subsequent obstruction of justice.”

As special prosecutor Robert Mueller’s investigation has veered closer to President Trump personally, House and Senate Republicans began attacking the credibility of the investigators, and now they’re demanding investigation of a prime witness.

It is a cause for serious concern that Grassley and Graham are using the threat of criminal prosecution to silence Christopher Steele rather than determining whether the information he produced in the so-called dossier can be confirmed. Rather than consider the message, they prefer to attack the messenger.

The fundamental issue here is whether a foreign power, Russia, interfered in a U.S. election. Mueller’s job is to determine whether laws were violated in the process. But using criminal law to punish the person who discovered this possible interference is a distortion of legal process for a political reason—to avoid an inconvenient question.

And that is why I am also uncomfortable with the Democrats’ enthusiasm for exploring psychiatric opinions—if not formal diagnoses—of Donald Trump. It is clear that his intellectual and cognitive abilities are sharply limited and perhaps becoming more so. The more we learn about his odd behavior under pressure, the more we should worry about him and honestly confront the questions his behavior raises.

But that is a long way from implying clinical diagnoses. If the president’s voice is to be disqualified on psychiatric grounds without formal diagnosis, his critics’ voices could be disqualified on the same grounds. Then it would be a short step for his more extreme defenders to demand confinement of his critics. It is not a precedent we should set.

Dr. Bandy X. Lee, a Yale psychiatrist who has expressed concern about Trump’s mental stability, makes a strong case for considering the president’s condition in public. Her meeting last month with a group of Democratic lawmakers—and one Republican—put the use of psychiatry in politics on the table for discussion.

One would like to believe we are still a long way from locking dissenters up in psychiatric hospitals, but there are members of the administration who may be capable of such a proposal. One has already suggested arresting California officials for protecting their state’s sanctuary status.

It is skating perilously close to the edge to use either criminal charges or psychiatric diagnoses to solve political problems.

If Trump is to be removed from the presidency for mental instability or breaking the law it must be done by transparently constitutional means—that is, 1) by the electoral process, 2) by impeachment, or 3) under the 25^th Amendment. Any of these would require a seismic shift in Republican opinion and thus seem unlikely unless his behavior becomes so bizarre that even his supporters can no longer defend him.