Rep. Paul Ryan, R-Wis., on Friday dressed down IRS Commissioner John Koskinen over the agency's recent mishandling of subpoenaed emails, its targeting of conservative groups and its consistent pattern of stonewalling congressional investigators.

"This is unbelievable!" an angry Ryan said. "The apology that ought to be given is to the American taxpayer. ...

"I don't believe it," he added. "That's your problem. Nobody believes you. ...

"... You can reach into the lives of hardworking taxpayers, and with a phone call, an email or a letter, you can turn their lives upside down. You ask taxpayers to hand us seven years of their personal tax information in case they're ever audited, and you can't keep six months worth of employee emails? ..."

Koskinen responded: "I have a long career. That’s the first time anybody has said they do not believe me."

"I am willing to stand on our record," the commissioner added.

Ryan stood by his earlier claim: "I don't believe you."