Here's a quick summary of the latest news: WHAT YOU NEED TO KNOW — Trump is predicting his impeachment fight with House Democrats could end up at the Supreme Court. His lawyers sent a letter to House Democratic leaders Tuesday declaring a full halt to cooperation with what the administration termed an "illegitimate" probe, in part because a formal vote has not taken place.
—The combative White House letter vowing to defy the "illegitimate" impeachment inquiry has actually put Trump on a more certain path to charges. His refusal to honor subpoenas or allow testimony is likely to play into a formal accusation against him.
—For the first time, Democratic presidential candidate Joe Biden called for Trump's impeachment , accusing the president of abusing the powers of his office to help his own reelection. The impeachment inquiry is rooted in Trump's unfounded accusations that the former vice president and his son had nefarious dealings in Ukraine.
—Vice President Mike Pence says he is working with the White House counsel's office to release transcripts of his own calls with Ukranian President Volodymyr Zelenskiy. He says the phone conversations help exonerate Trump of any wrongdoing.
When the House returns from a recess next week, Democrats plan to hold high-profile votes on legislation designed to improve the security of elections and prevent foreign interference.
NUMBERS THAT MATTER
33: the number of years that career diplomat Marie Yovanovitch has worked at the State Department.
Yovanovitch, whom President Donald Trump called "bad news" in his July 25 call with Ukrainian President Volodymyr Zelenskiy, spent three years as U.S. ambassador to Ukraine before being recalled in May. Her tour has also included stints in Armenia, Kyrgyzstan, Somalia, Russia, Canada and the United Kingdom.
Trump and his surrogates have painted Yovanovitch as a rogue State Department employee with an anti-Trump political bias, though her colleagues say she is smart, meticulous and reserved. Her ouster came amid attempts by Trump attorney Rudy Giuliani to press Ukraine into investigate Democratic presidential candidate Joe Biden and his son. Those efforts triggered the impeachment inquiry.
Yovanovitch is due Friday on Capitol Hill to testify before House investigators in the probe. Another State Department colleague, EU ambassador Gordon Sondland, was slated to testify earlier this week but was barred from appearing by the administration.
Speaking in New Hampshire, Joe Biden said Wednesday for the first time that Trump should be impeached, not only for his actions but for "the threat the president poses to the nation."