Key witness in the impeachment inquiry Marie Yovanovitch retires from the State Department after being ousted following an apparent smear campaign

• Former US ambassador to Ukraine Marie Yovanovitch announced her retirement from the State Department on Friday.
• Yovanovitch emerged as a key witness in Trump's impeachment inquiry after testifying she was the target of a smear campaign amid Trump's shadow diplomacy in Ukraine.
• The impeachment inquiry began due to a whistleblower complaint made public in September, alleging that Trump used his political power for personal gain.
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Former US ambassador Marie Yovanovitch, a key witness in Trump's impeachment inquiry, announced Friday that she is retiring from the State Department.

Yovanovitch emerged as a crucial figure during the impeachment hearings after she testified to the House that she was abruptly ousted from her position as ambassador to Ukraine, following what she described as "a smear campaign."

The impeachment inquiry began due to a whistleblower complaint made public in September, alleging that Trump used his political power for personal gain. The complaint centers on a July 25 phone between Trump and Ukrainian President Volodymyr Zelensky, in which Trump asked Zelensky to do him a favor and discusses the Bidens and a debunked 2016 election conspiracy theory.

Trump was impeached in December on charges of abuse of power and obstruction of Congress after evidence suggested he withheld military aid to Ukraine in exchange for an investigation into former Vice President Joe Biden and his son Hunter Biden, who sat on the board of Ukrainian energy company Burisma.

Trump and his attorneys have denied any wrongdoing. The president has maintained that his call with Zelensky was "perfect."

Trump's personal lawyer and former mayor of New York, Rudy Giuliani, was a central figure of the whistleblower's complaint. Yovanovitch was ousted after Trump and Giuliani, carried out a smear campaign against her based on false allegations that she was anti-Trump. In fact, Yovanovitch and other witness testified, Giuliani wanted her removed because she was a roadblock to his efforts to pressure Ukraine.

She was abruptly recalled from her position in May of last year.

One of Giuliani's associates, Lev Parnas has said that he was involved in both the smear campaign and the pressure campaign against President Zelensky.

Documents released by the House Intelligence Committee earlier this month revealed possible surveillance of the former ambassador. She was also referred in text messages in derogatory terms. The evidence prompted Yovanovitch's lawyer to call for an investigation.

• Read more:
• Ukraine launches criminal investigation into alleged surveillance of US Ambassador Marie Yovanovitch
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• Lawyer for diplomat Marie Yovanovitch demands investigation after explosive documents suggest she was surveilled in Ukraine