As the joint House panel investigating the impeachment of President Donald Trump continues its work, House Speaker Nancy Pelosi today today released a four-page summary of the case for impeachment.

The document, first reported by the Washington Post, is not a legal argument but rather a summary of key points from a whistleblower complaint, text of a July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky, and excepts from text messages released to Congress by former Ambassador Kurt Volker.

Trump's Ambassador to the European Union, the Portland hotelier Gordon Sondland, is mentioned frequently in Pelosi's document.

Sondland has reportedly played a central role in communications between the White House and Ukraine. In his testimony last week, Sondland attempted to distance himself from Rudy Guliani, Trump's personal attorney, without throwing Trump under the proverbial bus.

Here's how Pelosi characterized Sondland's role:

"Text messages between Ambassadors Kurt Volker, Gordon Sondland and Bill Taylor paint the picture of a President who waged a months-long pressure campaign to shake down Ukraine for his own personal political gain, potentially using a White House pre-sidential visit and critical military assistance to Ukraine as leverage," Pelosi writes.

Read Pelosi's document here.