WATCH: Nunes’ full questioning of Vindman and Williams | Trump’s first impeachment hearings

Trump's first impeachment - 2020 Rep. David Nunes, the ranking member of the House Intelligence Committee, questioned Lt. Col. Alexander Vindman, an Army officer who works for the National Security Council, and Jennifer Williams, an aide to Vice President Mike Pence, on Nov. 19, in a public hearing as part of the impeachment inquiry into President Donald Trump. In his line of questioning, Nunes attempted to glean more information that House Intelligence Committee Chairman Rep. Adam Schiff said could lead to revealing the identity of the whistleblower. Vindman told Nunes that his counsel suggested that he not answer questions or "provide specifics" about members of the intelligence community. Vindman's counsel spoke up saying he was following the rules set by Schiff and the committee. Schiff interjected during Nunes' questioning to say, "These proceedings will not be used to out the whistleblower." Vindman and Williams both listened in on a July phone call in which Trump asked the president of Ukraine to investigate former vice president and 2020 presidential candidate Joe Biden and his son, Hunter. For more on who’s who in the Trump impeachment inquiry, read: https://www.pbs.org/newshour/politics/whos-who-in-the-trump-impeachment-inquiry Stream your PBS favorites with the PBS app: https://to.pbs.org/2Jb8twG Find more from PBS NewsHour at https://www.pbs.org/newshour Subscribe to our YouTube channel: https://bit.ly/2HfsCD6 Follow us: Facebook: http://www.pbs.org/newshour Twitter: http://www.twitter.com/newshour Instagram: http://www.instagram.com/newshour Snapchat: @pbsnews Subscribe: PBS NewsHour podcasts: https://www.pbs.org/newshour/podcasts Newsletters: https://www.pbs.org/newshour/subscribe