Vindman and Williams testify that Biden-Ukraine allegations lack credible evidence

Lt. Col. Alexander Vindman and Jennifer Williams testified during Tuesday's impeachment hearing that the allegations claiming that the Biden family engaged in improper business dealings in Ukraine lack credible evidence.

The big picture: The allegations against the Bidens form a key concern for the impeachment inquiry regarding President Trump's July 25 call with Ukrainian President Volodymyr Zelensky. Vindman and Williams, who both listened to the call, testified that they were concerned by the fact that Trump mentioned the allegations.

Go deeper: Live updates from the Vindman-Williams impeachment hearing