House Intelligence Committee Chairman Adam Schiff (D-Calif.) opened the Democratic impeachment hearings against President Trump on Wednesday, saying among other things that he does not know the identity of the “whistleblower” intelligence officer who triggered the impeachment.

“I do not know the identity of the whistleblower and I’m determined to make sure the identity is protected,” Schiff said.

In his long opening statement on President Donald Trump, Schiff placed particular emphasis on the Trump administration’s handling of the Ukraine Case, referring to an alleged obstruction.

“Although we have learned a great deal about these events in the last several weeks, there are still missing pieces,” Schiff said. “The president has instructed the State Department and other agencies to ignore congressional subpoenas for documents. He has instructed witnesses to defy subpoenas and refuse to appear. And he has suggested that those who do expose wrongdoing should be treated like traitors and spies,” he said, Daily Caller reported.

President Trump wrote on his Twitter at the end of September that Schiff could be arrested for treason because he “illegally made up a FAKE & terrible statement, pretended it to be mine as the most important part of my call to the Ukrainian president, and read it aloud to Congress and the American people. It bore NO relationship to what I said on the call.”

Hearings in the public phase of President Trump’s impeachment began today, Nov. 13, with some key testimonies.

The impeachment is a controversial process against President Donald Trump, which claims that he would have called the Ukraine president asking him for an alleged “favor” to investigate former Vice President Joe Biden, who is one of his political rivals in the 2020 elections.

However, the White House emphatically denied those accusations and published transcripts of talks between President Donald Trump and the Ukrainian president.

The conversation shows that President Trump did not pressure or offer any financial compensation to Ukraine to investigate the son of Joe Biden, who was involved in a case of corruption of the main gas company in the European country.