Free Speech, Due Process, and Other Constitutional Limits in Senate Impeachment Trials

by Michael C. Dorf 

[**Updated to acknowledge two articles I neglected to cite in the initial version:]

After four years that felt like four lifetimes and a post-election eleven weeks that felt like eleven years, Inauguration Day is finally here. My new Verdict column addresses one of the challenges that will now confront President Biden and other rational Americans: the fact that so many people believe in dangerous nonsense. I suggest that the reasons for such beliefs are pretty deeply rooted in human psychology. The political power of conspiracy theorists and the craven politicians who do their bidding might not derail the Biden legislative agenda, but the conspiracy-theory-believing Americans themselves will make it harder to accomplish some of the urgent tasks that require public buy-in.

Now I want to shift gears and discuss the upcoming Trump Senate impeachment trial--which is being described by some as another potential obstacle to the Biden agenda, if for no other reason than that it will distract the Senate from other business. I believe that particular obstacle can and should be overcome by expeditious scheduling by soon-to-be-Majority Leader Schumer. That said, interesting constitutional questions await in the Senate impeachment trial.

In a recent essay, I offered three reasons why the free-speech defense suggested by some commentators should not avail Trump in his Senate impeachment trial: (1) Non-criminal conduct can be the basis for impeachment, so it does not matter whether Trump's speech at the January 6 rally preceding the storming of the Capitol and the course of conduct that led up to it amounted to a crime; (2) Trump's goal in fomenting violence may have been to create a pretext for martial law and the delay or cancellation of Biden's inauguration, which would be a separate ground for impeachment; and (3) in any event, Trump did commit the crime of incitement of violence, which, applying the Brandenburg test, was not shielded by the First Amendment.

In response to my prior essay, a colleague asked me an interesting set of questions about the relation between (1) and (3). Granting that non-criminal conduct can be the basis for impeachment, the colleague asked, is the fact (or not) of First Amendment protection irrelevant to impeachability? More broadly, to what extent, if any, do constitutional rights apply in a Senate impeachment trial? I'll address both of those questions, along with some further wrinkles involving the 1993 SCOTUS decision in the Judge Walter Nixon Case, which forecloses judicial review of impeachment procedures.

(1) Free Speech

There are things a president might say that are protected free speech in the sense that neither he nor anyone else could be made to suffer a penal consequence for them in the conventional sense but are nonetheless impeachable. Lying about a sufficiently consequential matter would be an example. Under United States v. Alvarez, political lies cannot generally be the basis for criminal liability. Still, we can imagine a presidential lie that would be a fair basis for impeachment.

Suppose that in 2002: (a) President George W. Bush had before him incontrovertible evidence that Saddam Hussein had no active nuclear program; (b) nonetheless, Bush wanted to invade Iraq because he thought it would shake up the Middle East map in a way that would advance US interests; (c) but Bush knew that announcing his true motivation would rob him of support in Congress; so (d) Bush and his associates repeatedly said "Saddam is on the verge of acquiring nukes" for the purpose of obtaining a congressional Authorization for Use of Military Force, resulting in a war in which thousands of US servicemen and women, as well as hundreds of thousands of Iraqis, perished--and ISIS was spawned.

With the probable exception of (a), all of the propositions in the foregoing paragraph are true. (Proposition (b) is true in the sense that shaking up the Middle East map was a motive for the Bush administration's push for the Iraq War, even if it wasn't necessarily the only motive.) As to (a), I think Bush lacked clear evidence of the end of the Iraqi nuclear program, so he was exaggerating and/or guessing rather than actively lying. However, if (a) were true, then I believe that under such circumstances, Bush's lies would be a constitutionally permissible basis for impeachment--even though the same lie told by a private citizen, even an influential one like a talk-radio host, could not be a basis for criminal liability.

Part of what I'm saying here is simply that the First Amendment has different implications for different sanctions. For example, New York Times v. Sullivan permits civil liability for defaming public figures by knowingly telling reputation-damaging lies about them (or by making false statements recklessly), but it's generally accepted that the First Amendment does not permit criminal libel. Likewise, we might think that impeachment is like civil liability; it's available in some circumstances in which the First Amendment bars criminal liability.

Here's another example: Suppose that throughout his presidency, Donald Trump publicly used racial epithets repeatedly and in his official as well as unofficial statements. Hate-speech is constitutionally protected against criminal sanction, but I nonetheless think this conduct would be impeachable.

That is not to say that merely offensive statements would necessarily be a proper basis for impeachment. Here, as elsewhere, Trump pushed the edge of the envelope with his demeaning language (e.g., calling Elizabeth Warren "Pocahontas") and use of terms that are widely but not yet universally regarded as inappropriate (e.g., insisting on using the term "illegal aliens" rather than "undocumented immigrants"). It's clear from when the House did and did not impeach Trump that his offensive language was not regarded as warranting impeachment, but I don't think that reflects an outright prohibition on impeachment based on hate-speech.

Suppose that Trump had used the n-word repeatedly and in reference to specific people in speeches, official documents, and on Twitter. I suspect that even many people now arguing that speech falling short of incitement cannot be the basis for impeachment would withdraw the objection. Why? Because it would reveal an attitude grossly inconsistent with the obligation to take care that the laws are faithfully executed--as those laws include key provisions demanding that people be treated equally.

A great deal more could be said about the limits, if any, the First Amendment places on what can be a basis for impeachment. Professor Kate Shaw usefully albeit briefly addressed this issue in a book review essay on the Take Care blog and in two law review articles on presidential speech (here and here), pointing to the role of speech in articles of impeachment against Presidents Andrew Johnson and Richard Nixon. In a 2020 article looking back on Trump's first impeachment, she discussed First Amendment arguments made during those impeachments as well as the Clinton impeachments, cautiously suggesting a conclusion along the lines above: offensive presidential speech by itself probably isn't impeachable but could rise to that level where part of a pattern of other conduct. Though less focused on the historical precedents, a recent book by Professor Frank Bowman reached roughly the same conclusion. Should Trump's defense rely on First Amendment arguments, perhaps we can expect Professors Shaw and Bowman to lend the Senate their expertise. 

(2) Other Constitutional Limits (Mostly Due Process)

What about other constitutional limits? Some pretty obviously should apply to an impeachment proceeding. Suppose that not-at-all-insane House member Marjorie Taylor Greene filed articles of impeachment against President Biden, not for being a child-molesting lizard-man but "for being a Papist." Impeaching any officer of the United States based on the officer's religion would violate the Religious Tests Clause of Article VI as well as the Free Exercise and Establishment Clauses of the First Amendment. Likewise, were Vice President Harris impeached for being of African or Indian descent, that would be a clear violation of the equal protection component of the Fifth Amendment's Due Process Clause.

Speaking of due process, that's the constitutional right most likely to be implicated by a Senate impeachment trial. What process is due depends on context. In criminal cases, in which the defendant stands to be deprived of liberty or even life, we have a panoply of protections such as the right to counsel, to cross-examine witnesses, and to be convicted only upon proof of guilt beyond a reasonable doubt. The process for a Senate impeachment trial, by contrast, is quite under-specified by the Constitution, which requires only that Senators be on oath or affirmation, that the Chief Justice presides over a presidential impeachment, and that a 2/3 vote is required for conviction. The Senate has additional rules, of course.

The Judge Nixon case makes clear that just what constitutes a trial is left to the Senate. Judge Nixon had argued that the presentation of evidence in a committee followed by argument in the Senate did not count as a "trial." A unanimous Court rejected that claim. Justices White and Blackmun said that trial by committee followed by debate on the record in the full Senate counted as a trial. For the majority, however, the question was non-justiciable. Thus, as a technical matter, the opinion for the Court by Chief Justice Rehnquist leaves open the possibility that the procedure used in the Judge Nixon case was unconstitutional but that the determination of that legal conclusion rested in the unreviewable judgment of the Senate.

Nevertheless, it is difficult to read the Nixon case without coming away with the conclusion that all nine Justices thought that what the Senate did was perfectly fine, regardless of whether it was reviewable. What about more questionable procedures?

In the first Trump impeachment, the Senate heard no new evidence, relying on the record as it was developed in the House. However, Trump's legal team did not object. Indeed, it was Trump-allied Republican Senators who made the decision not to hear new evidence over the objections of all Democratic Senators and two Republicans. Suppose that in the second impeachment trial Trump's team wants to introduce relevant evidence but that the Senate (now in Democratic control) decides it doesn't want to hear any evidence--perhaps because (a) just about everything Trump did was in plain sight, so there's no contested question of fact to which evidence would be relevant; and (b) between confirming Biden's nominees and considering urgent legislation, there are too many other demands on the Senators' time. Would the refusal to allow evidence violate Trump's due process rights?

I think the answer depends on the nature of the evidence. Imagine that Trump's team had credible witnesses who wanted to testify that Trump made private statements during or after the insurrection expressing surprise at what was happening or testimony from others in the chain of command indicating that, contrary to all appearances, Trump really was trying in good faith to order a mobilized forceful response while it was occurring. In a conventional criminal trial for incitement, the Sixth Amendment would entitle him to present his witnesses.

By its express terms, the Sixth Amendment applies only in "criminal prosecutions," and a Senate impeachment trial is not a criminal prosecution. However, the Fifth Amendment's Due Process Clause contains no such limitation. Stripping someone of the right to hold further office is pretty clearly a deprivation of liberty or property to which it does apply. Hence, for the same sort of reason that the Fourteenth Amendment's Due Process Clause incorporates the Sixth Amendment right to present a defense in state criminal trials, we should conclude that when a Senate impeachment trial defendant invokes the Fifth Amendment's Due Process Clause, there is a right to present relevant exculpatory evidence.

Accordingly, I think the Senate should conclude that due process does entitle Trump to an opportunity to present exculpatory relevant evidence, if there is any. Nonetheless, that conclusion comes with two important caveats.

The first caveat is implicit. A judge in a criminal trial does not have to permit defense witnesses to testify about whatever the defense wishes. Rules of evidence permissibly exclude irrelevant material. Similarly, purported expert witnesses who are in fact charlatans or cranks need not be permitted to testify.

Second, whatever procedures the Senate decides to use to conduct the trial and whatever evidence it admits would not be subject to judicial review. The Senate--and the Senate alone--is the judge of how to proceed.

In the Judge Nixon case, Justice Souter said that he thought that in an extreme enough case, Senate impeachment procedures would be reviewable. He gave the example of a Senate conviction based on a coin toss. Justice White's concurrence (endorsed on this point by Justice Souter) gave the example of an officer being impeached merely for being "a bad guy." Nonetheless, the majority opinion finding the case to present a non-justiciable political question was unequivocal: Senate impeachment verdicts are not subject to judicial review, full stop. If a Senate impeachment trial resulting in conviction based on a coin toss or a mere conclusion that the impeached officer is a "bad guy" is not subject to judicial review, then of course an officer convicted by the Senate after it rejected the officer's proffer of evidence is not reviewable.

Is the Judge Nixon case completely unequivocal? Would the courts treat as non-justiciable even a Senate conviction and removal of an officer on a clearly unconstitutional ground--as in my example above of a conviction that violates the Constitution's three Religion Clauses? Maybe.

In yet another concurrence in the Judge Nixon case, Justice Stevens said that the reason to reject justiciability in the coin toss example was that it would never occur. That's probably right, but I suppose the Senate could test the question by accepting Rudy Giuliani's suggestion of trial by combat--although it's not clear that judicial review on behalf of the losing party to such a contest would serve much purpose.