House Democrats have laid out the constitutional grounds for their case to impeach President Donald Trump, as the process gathers pace.
A report by the judiciary committee setting out the legal and historical basis for impeachment comes ahead of Monday's public hearing to consider evidence against Mr Trump.
A vote on articles of impeachment could be held as early as next week.
On Saturday, Mr Trump again described the process as a "witch-hunt".
The impeachment process began in September after an anonymous whistleblower complained to Congress about a July phone call by Mr Trump to the president of Ukraine, in which the president appeared to tie US military assistance to Ukraine launching investigations which would help him politically.
Democrats say that that this amounted to inviting a foreign power to intervene in the US election to help the president win another term.
The House Judiciary Committee's 52-page report, written by its Democratic staff, lays out what Democrats see as the constitutional argument for impeaching the president.
Unlike a recent report from the intelligence committee, it does not present evidence and testimony against him - but rather builds the case that will be made about how the founding fathers conceived impeachment and when it is justified.
It also aims to rebut some of the key defences made by Republicans and the White House against how the process has been conducted.
"The Framers [America's founding fathers] worst nightmare is what we are facing in this very moment," tweeted Jerry Nadler, the Democratic chairman of the judiciary committee.
"President Trump abused his power, betrayed our national security, and corrupted our elections, all for personal gain. The Constitution details only one remedy for this misconduct: impeachment."