Does a presidential impeachment inquiry allow the House to obtain documents relevant to its inquiry (such as a president's tax returns) more quickly? Do impeachment inquiries change anything relating to the subpoenaing of such documents?
Does a presidential impeachment inquiry give the House additional powers to obtain documents more quickly?
Apparently no additional powers to obtain documents more quickly; but access to more documents1.
How Congress Sets the Rules for Impeachment
Both the U.S. House of Representatives and the U.S. Senate have the right to make their own rules governing their procedure, and to change those rules. Under current rules, the actual impeachment inquiry begins in the Judiciary Committee of the House of Representatives. That Committee holds hearings, takes evidence, and hears testimony of witnesses concerning matters relevant to the inquiry. Typically, as occurred in the case of President Nixon, there will also be a Minority Counsel who serves the interest of the party not controlling Congress.
Witnesses are interrogated by the Committee Counsel, the Minority Counsel, and each of the members of the House Judiciary Committee. The Committee formulates Articles of Impeachment which could contain multiple counts. The Committee votes on the Articles of Impeachment and the results of the vote are reported to the House as a whole. The matter is then referred to the whole House which debates the matter and votes on the Articles of Impeachment, which may or may not be changed. If the Articles of Impeachment are approved, the matter is sent to the Senate for trial.
The Impeachment Process in the House of Representatives, updated August 12, 2019:
The standing rules of the House that affect committee investigations apply as well to impeachment investigations by the Judiciary Committee. A resolution authorizing an impeachment investigation might place additional limitations, or grant additional authorities, to the committee. In addition, the committee itself might adopt rules specific to an impeachment inquiry. It has not been unusual for the Judiciary Committee to authorize subcommittees or to create task forces to conduct impeachment investigations, and in that case the full committee would establish the authority of the subcommittee or task force.
Investigation and Hearings
Under House Rule XI, committees have the authority to subpoena persons or written records, conduct hearings, and incur expenses (including travel expenses) in connection with investigations. Rule XI, clause 2(h)(2), requires two committee members to take testimony or receive evidence. In past impeachment proceedings, the House has agreed to resolutions authorizing committee staff to take depositions without Members present, and the Judiciary Committee has agreed to internal guidelines for the mode and conduct of depositions.
Hearings are generally public, but they could be closed pursuant to regular House rules that allow the committee to agree, by holding a vote in public session with a majority of the committee present, to close a hearing for three specific reasons: the evidence or testimony would endanger national security, compromise sensitive law enforcement information, or would tend to “defame, degrade, or incriminate the witness.” Again, the resolution authorizing an impeachment investigation could alter these procedures.
There appears to be no particular difference with any other hearing before the Judiciary Committee; though, as noted above some rules may be changed for impeachment. How the committee responds to reluctant witnesses may be different.
The U.S. House Committee on the Judiciary, also called the House Judiciary Committee, is a standing committee of the United States House of Representatives. It is charged with overseeing the administration of justice within the federal courts, administrative agencies and Federal law enforcement entities. The Judiciary Committee is also the committee responsible for impeachments of federal officials. Because of the legal nature of its oversight, committee members usually have a legal background, but this is not required.
In the 116th Congress, the chairman of the committee is Democrat Jerry Nadler of New York, and the ranking minority member is Republican Doug Collins of Georgia.
The committee was created on June 3, 1813 for the purpose of considering legislation related to the judicial system. This committee approved articles of impeachment against Presidents in three instances: the impeachment of Andrew Johnson (1868), the impeachment process against Richard Nixon (1974), and the impeachment of Bill Clinton (1998).
1 Access to additional documents.
Under current rules, Congressional committees may request disclosure of grand jury documents under the following rule:
(E) The court may authorize disclosure-at a time, in a manner, and subject to any other conditions that it directs- of a grand-jury matter:
(i) preliminarily to or in connection with a judicial proceeding
It being the case that an impeachment inquiry fits the above description.
A petition to disclose a grand-jury matter under Rule 6(e)(3)(E)(i) must be filed in the district where the grand jury convened (Rule 6(e)(3)(F)).