Legal Sidebari
Impeachment Investigations: Law and Process
October 2, 2019
Speaker Pelosi announced last week that the House “is moving forward with an official impeachment
inquiry.” Although the Speaker’s statement did not address precisely how the House will proceed, it is
noteworthy not only because the House has so rarely investigated a President for the purpose of
impeachment, but also because an impeachment investigation has usually been an early step in a
constitutional process that could ultimately result in the removal of the subject of the inquiry from office.
This Sidebar identifies procedural options for the House as it proceeds with an impeachment
investigation. The Sidebar also describes some of the ways in which an impeachment investigation, as
compared to a more traditional investigation for legislative or oversight purposes, might bolster the
House’s ability to obtain, either voluntarily or through the courts, information from the executive branch.
The Sidebar also briefly describes possible future steps that might follow an impeachment inquiry,
including possible action by the Senate.
The Mechanics of House Impeachment Investigations
The House has a number of options for proceeding with its impeachment investigation, as the manner by
which the body chooses to implement its impeachment powers is textually and historically committed to
the House’s own discretion. It could, adopt a resolution that explicitly authorizes the House Judiciary
Committee (or another committee) to conduct an investigation to determine whether there are sufficient
grounds to impeach the President and, if warranted, report articles of impeachment to the House. Or the
House could establish and empower a select investigative committee to handle this duty, perhaps giving
the body broad jurisdiction over all relevant aspects of the allegations against the President. In either case,
an authorizing resolution typically makes explicit that the investigating committee is acting with the
imprimatur of the House and exercising the full panoply of the House’s constitutionally based
investigative and impeachment powers. Authorizing resolutions also provide a means for the House to
both direct the scope of an impeachment inquiry and, if desired, provide the investigating committee with
additional tools to enable a thorough and expeditious investigation. While House rules already provide
standing committees with several compulsory mechanisms to gather information, authorizing resolutions
for impeachment inquiries have generally conferred additional investigatory tools to a committee, such as
the authority to compel responses to interrogatories.
Rather than considering a resolution that expressly authorizes an impeachment inquiry of the President,
the House might take the position that such an inquiry is already underway, and opt to allow its
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committees to continue their ongoing investigations or begin new inquiries using their existing
investigative tools and authorities. It is because those existing investigative tools and authorities have
grown over time—and now include allowing committee chairs to issue subpoenas and committee staff to
take depositions—that the practical need for obtaining additional powers from the House may have
diminished. Both the Speaker’s initial statement, in which she specified that the House will “direct[] our
six committees to proceed with their investigation under that umbrella of impeachment inquiry,” and
subsequent statements suggesting that the Intelligence Committee will continue to focus on recent
whistleblower accusations, appear to suggest that the House may follow this type of approach, with an
impeachment investigation that encompasses ongoing investigations by various committees.
If the House takes no new action on authorizing the investigation, the Speaker’s statement that the House
is launching an “official impeachment inquiry” is unlikely to put to rest the debate among some inside
and outside of Congress about how to properly characterize various committees’ ongoing investigations
of possible executive misconduct, including continuing investigations by the House Judiciary and
Intelligence Committees. This debate centers on the proper role of the House in initiating impeachment
investigations. For example, while Chairman Nadler has stated that the Judiciary Committee is already in
“formal impeachment proceedings” and the Committee has adopted “procedures” for the “presentation of
information in connection with the Committee’s investigation to determine whether to recommend
articles of impeachment,” Ranking Member Collins has asserted that “House precedent requires the full
House approve a resolution authorizing the Judiciary Committee to begin an impeachment inquiry.” Nor
does it appear that the Speaker’s statement alone will necessarily prevent the Trump Administration from
arguing (as it is doing in pending litigation) that the House has not “expressly endorsed” the Judiciary
Committee’s impeachment investigation. The Speaker’s statement might be read to support those in the
House who believe authorization for an impeachment investigation has already been provided by prior
legislative actions, including, among other things, referring articles of impeachment to the Judiciary
Committee and authorizing House committees to exercise “any and all necessary authority under Article I
of the Constitution” in specified litigation matters.
Information Access in an Impeachment Investigation
However the House chooses to proceed, invocation of the impeachment power could strengthen the
House’s investigative authorities in a way that may improve the chamber’s ability to obtain information,
especially information the Trump Administration is withholding from various congressional committees.
As a practical matter, the significance of a possible exercise of the impeachment power, along with a
resulting increase in political and perhaps public pressure, may itself affect the Executive’s compliance
decisions. During the Nixon impeachment, the Judiciary Committee noted that “not one” subject of nearly
70 prior impeachment investigations “challenged the power of the committee conducting the
impeachment investigation to compel the production of evidence it deemed necessary.” President Andrew
Johnson, for example, voluntarily provided the Judiciary Committee with sensitive information during
that Committee’s impeachment investigation—including confidential communications with advisors and
information related to the use of his pardon and veto power. Presidents Nixon and Clinton also pledged
cooperation with House impeachment investigations. But an impeachment investigation is not a panacea
for access. Both Nixon and Clinton were later viewed by the Judiciary Committee as withholding relevant
evidence, when they either failed to comply with subpoenas or provided the House information believed
to be false or misleading.
That said, an impeachment investigation does provide the House with a unique tool of leverage in
information-access disputes with the Executive. For example, whereas the options available to a
committee to seek enforcement of a demand made to the executive branch in a traditional investigation
can sometimes be limited, in an impeachment investigation, a committee might more easily recommend
an article of impeachment for failure to comply with a committee subpoena. The Judiciary Committee did
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just that during both the Nixon and Clinton impeachment investigations, when both Presidents either
refused to comply with Committee subpoenas or provided incomplete or “false and misleading”
information.
Impeachment Investigation in the Courts: Executive Privilege
It is also possible that an impeachment investigation may, relative to a traditional oversight investigation,
provide the House with a stronger legal position in litigation to obtain information from the executive
branch. For example, an impeachment investigation may improve the likelihood of a court authorizing
committee access to grand jury materials. Investigating for purposes of impeachment may also relieve or
satisfy any possible limitations imposed by the requirement that a committee act with a “legislative
purpose.” But perhaps most significant, especially for purposes of the House’s current investigations, an
impeachment investigation may improve the likelihood that a committee will be able to overcome
executive privilege assertions made in response to congressional subpoenas.
Congress has long viewed itself as possessing broad authority to obtain information in furtherance of its
impeachment power. Indeed, during the Nixon impeachment investigation the Judiciary Committee
argued that an assertion of executive privilege “cannot be permitted to prevail over the fundamental need
to obtain all the relevant facts in the impeachment process.” As stated by the Committee:
Whatever the limits of legislative power in other contexts—and whatever need may otherwise exist
for preserving the confidentiality of Presidential conversations—in the context of an impeachment
proceeding the balance was struck in favor of the power of inquiry when the impeachment provision
was written into the Constitution.
But the Supreme Court has never addressed executive privilege’s application in either a traditional
oversight investigation or an impeachment investigation. In fact, because courts have a limited role in
adjudicating information-access disputes between the branches and arguably no role in adjudicating
impeachment matters, the federal courts as a whole have said very little about executive privilege in
traditional investigations and almost nothing about executive privilege in impeachment investigations.
It is clear, however, that executive privilege, even if found to cover subpoenaed information, does not
present an absolute bar to congressional access. Instead, courts must balance the Executive’s interest in
confidentiality against Congress’s need for (and, perhaps, the public interest in) disclosure of the
information. Perhaps the most significant judicial insight into this balancing approach comes from the
decision by the U.S. Court of Appeals for the District of Columbia Circuit (D.C. Circuit) in Senate Select
Committee v. Nixon. That case involved an effort by the Senate Watergate Committee to enforce a
subpoena issued to President Nixon for recordings of specific conversations he had with presidential
advisors in the Oval Office, thus squarely implicating aspects of executive privilege, but not in the context
of an impeachment investigation.
The court ultimately sided with the President, at least partly because the President had publicly released
transcripts of some of the tapes and the House Judiciary Committee had already obtained others. But in
non-binding dicta, the court also seemed to suggest that its analysis might have been different if the
subpoena had been part of the Judiciary Committee’s separate but “overlap[ing]” impeachment
investigation of the President, as that investigation “has an express constitutional source.” The Supreme
Court made a similar suggestion nearly a century earlier in Kilbourn v. Thompson, reasoning again in
dicta that while the House in that case lacked a valid legislative purpose to compel testimony, if an
investigatory purpose “had been avowed to impeach . . ., the whole aspect of the case would have been
changed.”
While these general statements suggest that courts might treat impeachment investigations differently
from traditional legislative investigations, they do not elaborate on how or why. Although not directly
articulated by the courts, there appear to be a variety of reasons a court may balance an impeachment
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investigation against an invocation of executive privilege in a manner that is more favorable to
congressional access.
For one, it might be argued that the importance of the impeachment function’s constitutional role in
addressing misconduct by federal officials and preserving the separation of powers requires that
impeachment investigations be afforded the utmost deference when weighed against executive branch
confidentiality interests. And the courts have suggested that the frequency with which forced disclosures
may occur in a particular context is an important factor in any executive privilege balancing. In short, the
courts have stated that when a given context is likely to provide only “infrequent occasions” of forced
disclosure, that fact “militate[s] against any substantial fear that the candor of Presidential advisers will be
imperiled” or the privilege seriously undermined. This line of reasoning suggests that a court may be
more willing to order disclosure to a committee engaged in a historically rare impeachment investigation
than it would to a committee in a much more common legislative investigation. Finally, the need for
specific factual evidence may be greater in an impeachment investigation than in a traditional
investigation. Whereas information gathered by Congress in carrying out its traditional legislative
functions, such as assessing whether legislation is required or whether an agency is carrying out its
mission appropriately, may be somewhat general in scope, impeachment investigations may necessitate a
more exacting factual record for more specific inquiries about the conduct of a particular official.
Possible Steps Following an Impeachment Inquiry
An impeachment investigation is just one of many stages of the constitutional process of impeachment
and removal—a process filled with numerous substantive and procedural hurdles. If an investigating
committee finds that there are adequate grounds to believe that the President or another impeachable
official has in fact committed an impeachable offense, specific articles of impeachment can be drafted for
consideration first by the committee and, if reported out of the committee, by the House. Although only
requiring majority support, proposed articles do not always receive approval, and are subject to
amendment or rejection during committee deliberations and in any subsequent consideration by the
House. For example, during the Clinton impeachment, the Judiciary Committee considered four separate
articles of impeachment. When originally considered by the Committee, Article IV, entitled “abuse of
power,” charged the President with willfully misleading the public, “frivolously and corruptly” asserting
executive privilege during the Independent Counsel investigation, and providing false and misleading
statements to Congress. The Judiciary Committee amended that article to remove the charges relating to
misleading the public and improperly asserting executive privilege. The paired down Article IV, though
approved by the Committee, then moved to the House where it ultimately failed.
What Must the Senate Do in Response to an Impeachment by the House?
Another question that might arise in a potential impeachment concerns the Senate’s role in the process.
The Constitution bestows on the House the power to impeach government officers, but grants the Senate
“the sole power to try all impeachments.” But that text does not in explicit terms require the Senate to
conduct a trial, nor does it define precisely what constitutes a trial in the first place.
Exactly what the Senate must do following an impeachment by the House is thus a subject of debate.
Relying on past historical practice, one might argue that, at least in the case of a presidential
impeachment, the Senate must conduct a trial and do so in a fashion similar to how it has done so in the
past. To date there have been two presidential impeachments (of Presidents Andrew Johnson and Bill
Clinton), and in both the Senate conducted a trial and ultimately voted to acquit the President. One might
also argue that, at least in certain circumstances, failure to conduct a trial would be an abdication of the
Senate’s duty in the impeachment process. But just as the Constitution bestows the “sole power” of
impeachment on the House, it similarly grants the “sole power” to conduct a trial with the Senate. The
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House, of course, thus enjoys discretion over whether to impeach in the first place; likewise, one might
argue that the Constitution also grants the Senate discretion over whether to conduct a trial.
But separate from any debate over whether the Senate is constitutionally required to conduct a trial of an
official impeached by the House, the current Senate impeachment rules are phrased in mandatory and
detailed terms. For example, once the Senate receives notice from the House that the managers have been
appointed to argue the case for impeachment in the Senate, “the Senate shall immediately inform the
House of Representatives that the Senate is ready to receive the managers for the purpose of exhibiting
such articles of impeachment.” Once the articles are presented to the Senate, “the Senate shall at 1 o’clock
afternoon of the day (Sunday excepted) following such presentation, or sooner if ordered by the Senate,
proceed to the consideration of such articles and shall continue in session . . . after the trial shall
commence (unless otherwise ordered by the Senate) until final judgment.” Perhaps for this reason, Senate
Majority Leader Mitch McConnell recently stated that if the House impeached the President, the Senate
would have “no choice but to take it up” under current Senate rules. On the other hand, the Senate may
waive or alter these provisions.
A further complication in examining the Senate’s duty in response to an impeachment is the substantial
discretion the Senate may have in determining what features an impeachment “trial” must include. Just as
the Constitution does not require the House to exercise its impeachment powers in any particular manner,
it similarly does not explicitly mandate that an impeachment trial encompass specific aspects beyond
mandating that the Chief Justice preside at trials of the President, Senators take an oath or affirmation
when sitting for the trial, and that a two-thirds vote is required to convict. In the impeachment trial of
Andrew Johnson, for instance, in which the Senate voted to acquit on three articles, the Senate did not
vote at all on various remaining articles. And in dismissing a challenge to how the Senate held a previous
impeachment trial of a federal judge, the Supreme Court has found the Constitution’s grant of a “sole
power” to conduct a trial “of considerable significance,” reasoning that its “commonsense meaning”
suggests that “the Senate alone shall have authority to determine whether an individual should be
acquitted or convicted” and do so “independently and without assistance or interference.” In the case in
question, the Court ultimately dismissed the challenge as presenting a nonjusticiable political question.
Consequently, at least as a practical matter, it appears that the Senate has considerable flexibility in
choosing how to structure an impeachment trial.
Author Information
Todd Garvey
Jared P. Cole
Legislative Attorney
Legislative Attorney
Disclaimer
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