Updated on Jan. 20 at 11:15 p.m. ET

The Senate is beginning a trial on whether or not to remove President Trump from office, a little over a month after the House voted to impeach him.

Read the latest news about the inquiry; listen to our special broadcast coverage.

While momentum toward impeachment had been building among Democrats for months, House Speaker Nancy Pelosi, D-Calif., announced an inquiry in September — after a whistleblower complaint about a White House phone call with Ukraine.

In a call with Ukrainian President Volodymyr Zelenskiy on July 25, Trump asked for an investigation into a debunked conspiracy theory about the 2016 election and into potential 2020 rival and former Vice President Joe Biden. The White House is also accused of withholding military aid to Ukraine for Trump’s personal political gain. Trump maintains that he has done nothing wrong.

The House conducted an inquiry that involved a series of closed-door depositions followed by open hearings with key witnesses, including career diplomats with expertise in Ukraine policy. The House Judiciary Committee then voted to recommend impeachment, and the full House voted to impeach on Dec. 18.

The Senate is voting on the rules of its trial on Jan. 21, and opening arguments are expected to begin the next day. At the end of the trial the Senate will vote on whether to remove Trump from office or acquit him.

The Articles

The House brought two articles of impeachment against Trump: abuse of power and obstruction of Congress.

“President Trump has acted in a manner contrary to his trust as President and subversive of constitutional government, to the great prejudice of the cause of law and justice, and to the manifest injury of the people of the United States,” the resolution reads.

Read the articles.

The Trial

Following the House vote to impeach, the Senate holds a trial. Republican and Democratic leadership have been fighting over what constitutes a “fair” trial and whether that includes witnesses who did not take part in the House’s investigation.

In the trial, members of the House serve as “managers” who make the case for Trump’s removal. The president has his own defense team, including White House counsel, outside attorneys and Republican members of the House.

After the proceedings, senators vote on whether to remove or acquit Trump, based on each article.

Read more about the trial process.

Who Was On The Call

The White House has not released a full list of participants on the July 25 call, but NPR has compiled a list of people identified so far. Here’s who they are.

Timeline: The Ukraine Affair

From Trump’s early focus on Ukraine in 2017, to the release of the whistleblower complaint on Sept. 26, here’s how we got to the impeachment inquiry.

Separately, here is a full timeline of the impeachment inquiry, including these key dates:

Dec. 11: House Judiciary begins debate on articles
Dec. 13: House Judiciary approves articles of impeachment
Dec. 18: Full House debates the articles and then votes to impeach
Jan. 16: House impeachment managers hand-deliver the articles to the Senate, a day after being appointed. U.S. Chief Justice John Roberts and senators are sworn in.
Jan. 21: Opening arguments begin in the Senate trial.

Who And What: Key People And Concepts

Since the original whistleblower complaint was released, the list of names of those connected to Trump’s call with Zelenskiy or to broader Ukraine policy has grown substantially.

From the president to career diplomats to private lawyers, here is a quick guide to people connected to the events being investigated.

Want to see the visual? Click here.

In-depth profiles and features:

• John Bolton: Democrats now have an unlikely ally
• Pat Cipollone: Trial turns spotlight on White House counsel
• Lev Parnas and Igor Fruman: A complicated web connects two Soviet-born businessmen with the inquiry
• Nancy Pelosi: How the House speaker unified a divided caucus
• Mike Pence: Inquiry will test a political path shaped by faith
• Rick Perry: How the energy secretary became a key figure
• Adam Schiff: The surprising face of the impeachment inquiry
• Gordon Sondland: The ambassador whose texts put him at the center of the Ukraine scandal
• Kurt Volker: Ex-U.S. special envoy to Ukraine caught in whirlwind of impeachment inquiry
• Marie Yovanovitch: How the former ambassador became a target in Ukraine
• Volodymyr Zelenskiy: How Ukraine’s president wound up in the middle
• Quid pro quo: From simple exchange to shakedown, here’s how the phrase evolved
• Trump and the CIA: How the relationship between Trump and his spy chiefs soured

Documents: Primary Sources

Written words are central to the Ukraine affair. The significance of the whistleblower’s original complaint and the White House’s record of its call with Ukraine are debated, but the text is public. Here are the documents to refer to as the inquiry proceeds:

Texts and memos

• Call: The White House memo of Trump’s July call with Zelenskiy (Sept. 25)
• Aid: The Pentagon letter on military aid to Ukraine (Sept. 25)
• Complaint: The whistleblower complaint (Sept. 26)
• Texts: Batch of texts between diplomats released by House Democrats (Oct. 4)
• Letter: A fact check of the White House legal argument (Oct. 9)
• The Other Call: The log of Trump’s April call with Zelenskiy (Nov. 15)
• The articles of impeachment: Abuse of power and obstruction of Congress (Dec. 10.)
• Judiciary report: House panel’s summary of the evidence (Dec. 16)
• Trump letter to Pelosi: Trump slams “partisan impeachment crusade” (Dec. 17)
• White House legal brief: Trump’s defense accuses Democrats of “dangerous perversion” of the Constitution (Jan. 20)
• Trial rules: Senate Majority Leader Mitch McConnell’s resolution (Jan. 20)

Corroborating the whistleblower complaint

The whistleblower’s complaint has largely been corroborated by witness testimony, public statements and media reports. Read an annotation of the document.

Transcripts of closed-door depositions

• Christopher Anderson, former special adviser for Ukraine negotiations
• Laura Cooper, deputy assistant secretary of defense for Russia, Ukraine and Eurasia
• Catherine Croft, former Ukraine adviser on the National Security Council
• David Hale, under secretary of state for political affairs
• David Holmes, political counselor at U.S. embassy in Kyiv
• Fiona Hill, former White House adviser on Russia
• George Kent, deputy assistant secretary for European and Eurasian Affairs
• Michael McKinley, former State Department adviser
• Philip Reeker, acting assistant secretary of State for Europe
• Mark Sandy, White House budget official
• Gordon Sondland, U.S. ambassador to EU
• William Taylor, acting U.S. ambassador to Ukraine
• Alexander Vindman, top Ukraine expert on the National Security Council
• Kurt Volker, former Ukraine envoy
• Marie Yovanovitch, ex-U.S. ambassador to Ukraine

Public hearings

Nov. 13: William Taylor, George Kent
Taylor Says Trump Asked About Ukraine ‘Investigations’

Nov. 15: Marie Yovanovitch
Yovanovitch Says Trump Comments In July Call Felt Like A ‘Threat’

Nov. 19: Jennifer Williams, Alexander Vindman, Kurt Volker, Tim Morrison
Impeachment Witness Testifies That Trump’s Ukraine Call Was ‘Improper’

Nov. 20: Gordon Sondland, Laura Cooper, David Hale
Sondland Says Top Trump Officials Knew Of Push For Ukraine Investigations

Nov. 21: Fiona Hill, David Holmes
Impeachment Hearings Wrap As Fiona Hill Slams GOP’s ‘Fictional’ Ukraine Account

Dec. 4: House Judiciary hearing on impeachment and the Constitution
Judiciary Committee Takes Up Impeachment In Hearing With Legal Scholars

Dec. 9: Presentation of the evidence for impeachment to Judiciary
Democrats Argue Trump Actions Are ‘Clear And Present Danger’

Special Coverage

NPR is airing special coverage at pivotal moments in the inquiry to help you make sense of it all. Listen to those broadcasts on your local public radio station. Find the archive of the audio here.

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