Transcript for Trump lashing out at democrats over Presidential investigations

President trump tonight is lashing out, as Democrats who now control the house have stepped up their oversight. The president calling it, quote, presidential harassment, saying the DEMs are, quote, going nuts. House speaker Nancy Pelosi pushing back tonight, calling the scrutiny on the president their constitutional spot, and tonight, one target? The president's taxes. ABC's Mary Bruce up on the hill. Reporter: Democrats in congress are kicking their investigations of the trump presidency into high gear. I think overwhelmingly the public wants to see the president's tax returns. Reporter: Unlike previous presidents, trums refused to release his returns. I'm not releasing the tax returns, becauses you know, they're under audit. Reporter: But now, Democrats have the power to go after them. We will ask the question, does the public have a need to know that a person seeking to hold the highest office in our country obeys the tax law? Reporter: With Democrats digging in, the president is lashing out, tweeting, "Unlimited presidential harassment. The DEMs and their committees are going nuts." Is there any concern that you're in danger of appearing like you're overreaching? Whatever the president says about us, he's projecting his own unruliness. He's a projector, and that's what it's about. Reporter: The house intelligence committee is launching a sweeping investigation into the president, his family, his finances and possible Russia ties. And tonight, a standoff between the house judiciary committee and the president's acting attorney general, Matthew Whitaker. Committee chairman Gerald Nadler threatened to subpoena white if he doesn't show up at a scheduled hearing tomorrow. Whitaker then refusing to appear unless the congressman drops that threat. All right, so, let's get to Mary Bruce live, because there are fast-moving parts on this story tonight. Just moments ago, Mary, the white house releasing a statement about the acting attorney general? Reporter: Yes, and David, the chairman here still isn't ruling out that subpoena, saying it depends on how Whitaker answers their questions, if he shows up here tomorrow. But tonight, the white house says the chairman is, quote, playing pointless political games. David? Mary bru thank you. Now, to an ABC news

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