Sunday on ABC’s “This Week,” House Intelligence chairman Rep. Adam Schiff (D-CA) said special counsel Robert Mueller had a “duty” to testify before Congress about his investigation into the 2016 election.

Schiff said, “I was disappointed to see such a profound reluctance to testify. I understand that. I think he has one last service to perform. It’s not enough merely to speak for 10 minutes and say, ‘I’m not going to answer questions for Congress and the American people.’ There are a great many things that are not in the report.”

He continued, “We want to find out what happened to those counterintelligence findings that were sent back to headquarters. And in terms of if the president is vulnerable of influence from Russia. Why the president can’t criticize Putin or take adequate steps to protect our elections. The American people have every need to have answered here. I hope Bob Mueller will answer, as painful as it may be, he has a final duty here to perform. Like any other witness and it’s my hope he’ll do so and it’s my hope that he’ll do so voluntary.”

Stephanopoulos asked, “If he doesn’t, subpoena?”

Schiff said, “That would be my recommendation. That’s decision we’ll have to make collectively and our leadership when there’s use of compulsion, because it may lead to litigation. That’s not how this process for Bob Mueller should end. He’s a dedicated public servant.”

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