Democrats, Pressing Abuse of Power Case, Delve Into Biden

To begin with, she said, the prosecutor, Viktor Shokin, was “widely perceived as corrupt,” and Mr. Biden was acting in accordance with official American policy, as well as the policy of the European Union, the International Monetary Fund and other international organizations in calling for his removal.

Moreover, Mr. Shokin had already let the Burisma investigation “go dormant,” Ms. Garcia said, so his ouster “would only increase the chance that Burisma would be investigated for possible corruption.” She asserted that neither the elder Mr. Biden nor his son had done anything wrong, and that American officials — and Mr. Trump — knew it.

“Every single witness who was asked about the allegations again said that Biden had nothing to do with it and it was false; they testified that he acted properly,” Ms. Garcia said, adding, “There is simply no evidence, nothing, nada in the record to support this baseless allegation.”

“In short,” she added, “President Trump asked for the investigation into Biden based on a made-up theory that no one agreed with. No one.”

It was, in effect, a defense of one of the Democrats’ leading 2020 presidential candidates and a potential challenger to the president. Mr. Schiff later volunteered that neither he nor his colleagues had a position on the Democratic presidential primary.

Mr. Schiff also brought Mr. Trump into the chamber — at least on video — to use the president’s own words against him, with a clip in which the president called both Bidens “corrupt” and called for Ukraine to start a “major investigation” into them.

“The president has confirmed what he wanted in his own words,” Mr. Schiff said. “He has made it clear he didn’t care about corruption, he cared only about himself. Now it is up to us to do something about it, to make sure that a president, that this president, cannot pursue an objective that places himself above our country.”