Senators voted to block four separate motions from Democratic leader Chuck Schumer to subpoena records and documents related to Trump's dealings with Ukraine.
House impeachment investigators released material that Parnas had turned over to them including text messages, photos and calendar entries.
His long day began in the familiar confines of the ornate marble-fronted Supreme Court building before he headed across the street to the US Capitol to preside over the full opening session.
Trump impeachment hearings in the Senate will be held six days a week, Monday through Saturday.
US President Donald Trump demonstrates his diplomatic power abroad as the Senate in Washington D.C. is slated to open his impeachment trial.