Key impeachment probe witness a 'no-show' in US Congress

WASHINGTON — The impeachment showdown in Washington took an urgent new tone on Monday as a key witness defied a US House subpoena to testify, leading Democrats to accuse President Donald Trump of obstructing Congress's work.

The White House seeks to block the appearance by ex-deputy national security adviser Charles Kupperman, who last week took the rare step of filing a lawsuit urging a court to decide on the "irreconcilable commands" of both the executive and legislative branches of government.

Democrats are keen to hear from Kupperman as he reportedly was on the July 25 telephone call between Trump and his Ukrainian counterpart in which the US leader pushed Kiev investigate his political opponents.

That request by Trump, and accusations he conditioned nearly $400 million in military aid to Ukraine on the political favor, form the basis of the impeachment inquiry that began five weeks ago and now threatens his presidency.

"He was a no-show," House Intelligence Committee Chairman Adam Schiff said of Kupperman, telling reporters that he and the other Democrats overseeing the probe rejected the lawsuit filed on Friday and were considering holding him in contempt.

"A private citizen cannot sue the Congress to try to avoid coming in when they're served with a lawful subpoena," Schiff said.

Schiff said he hoped Kupperman would do as nine previous witnesses, many of them career public servants, had done and testify despite White House orders not to.

White House opposition to Kupperman's appearance makes it clear "that they believe that his testimony would be incriminating of the president", Schiff added.

"Any acts of obstruction like this, any effort to prevent the Congress... from learning more about the president's misconduct will merely build a public case for obstruction of Congress by this president."

Kupperman served as deputy to former national security adviser John Bolton, who was reportedly deeply alarmed by what he saw occuring with Ukraine, and whom Democrats have indicated they want to hear from as part of the investigation.

Several other officials have already come forward, including Bill Taylor, the top US diplomat in Ukraine; Gordon Sondland, the US ambassador to the European Union who has worked extensively on Ukraine issues; and Marie Yovanovitch, who was US ambassador to Kiev until the Trump administration removed her.

While Kupperman stayed away, Sondland returned to Capitol Hill Monday for a second closed-door session.

Sondland had testified that Trump ordered US diplomats in May to involve his personal lawyer Rudy Giuliani in talks between Washington and the new administration of Ukraine President Volodymyr Zelensky.