Transcript for Texts show Trump admin pressured Ukraine to investigate Biden
Now to the new developments coming in. The house issuing a subpoena to the white house, pulling vice president pence. Asking for any Ukraine related documents, and now we're learning about the text Mary Bruce is on the hill. Reporter: Tonight, Democrats are now reaching deep into the white house, investigating the role of the vice president. Issuing a subpoena to Mike pence, demanding documents about "Any role you may have played" in the effort to pressure Ukraine to investigate the president's political rivals. We have concerns about the role the vice president played in this presidential extortion scheme. What are you going to tell them? Reporter: We're learning new details from the first eyewitness to testify before congress, former U.S. Envoy to Ukraine Kurt Volker. In his opening statement, obtained by ABC news, Volker describes a president obsessed with a debunked conspiracy theory that Ukraine, not Russia, meddled in the 2016 election to help Democrats. And Volker handed over a trove of text messages that appear to show top U.S. Officials dangling a potential white house visit as leverage to get Ukraine to investigate trump's rivals. In one text, Volker tells an aide to Ukrainian president zelensky, "Heard from white house. Assuming president Z. Convinces trump he will investigate, get to the bottom of what happened in 2016, we will nail down date for visit to Washington." That message was sent just hours before the phone call that sparked this impeachment inquiry, when trump personally asked the Ukrainian leader to, quote, "Do us a favor" and investigate the Democrats and Joe Biden. Even some Republicans say the texts are troubling. Some of the text messages individually is concerning. There's no doubt about that. Reporter: Volker says he tried to convince the president's personal lawyer Rudy Giuliani that Biden had done nothing wrong, telling lawmakers, "The suggestion that Biden would be influenced in his duties as vice president by money for his son simply has no credibility to me. I know him as a man of integrity." But those words seemed to have no effect. Why is it so hard to get Biden investigated? Mary, you're learning just moments ago, congress issued a subpoena to the white house? Reporter: Democrats just issued this subpoena for records related to Ukraine. Saying the president's actions have left them with no other choice. And if the white house continues to stonewall this, they say this will only boost the impeachment
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