On the heels of an expanded investigation brought by House Judiciary Committee Chairman Jerry Nadler, D-N.Y., famed attorney Alan Dershowitz warned Tuesday that House Democrats may have gone “too far” and could face lawsuits for allegedly abusing their oversight powers.

“Congress has a legitimate oversight function to perform but it has to make sure it doesn’t go too far. It can’t use that oversight function, which is really designed to help get legislation, in order to really prevent a president from finishing out his terms and acting. They’re interfering with the executive branch if they do so,” Dershowitz said on “Hannity.”

“A balance has to be struck between the legitimate function of Congress to investigate,” Dershowitz said. “The framers didn’t intend for Congress to become another prosecutorial branch, yet another investigative branch, they’re supposed to pass laws. So it seems to me these investigations look like they’re going too far.”

Nadler issued requests for information Monday from 81 people or organizations connected to President Trump. Among them: Vice President Pence, Trump’s son Donald Trump Jr. and son-in-law and senior adviser Jared Kushner.

Meantime, House Intelligence Committee Chairman Adam Schiff, D-Calif., has vowed to continue the investigation into Trump's Russia connections and finances for as long as necessary.

DAN BONGINO: DEMS TURN TO DESPERATE POLICE-STATE TACTICS

President Trump reacted Tuesday on Twitter calling Nadler's requests “harassment.”

“Nadler, Schiff and the Dem heads of the Committees have gone stone cold CRAZY. 81 (letters) sent to innocent people to harass them. They won’t get ANYTHING done for our Country!” Trump tweeted.

CLICK HERE TO GET THE FOX NEWS APP

Dershowitz, also a retired Harvard law professor, said those subpoenaed could possibly sue.

“If you go back to the cases in the 1950s, the courts sometimes did say, ‘look, Congress, you’ve gone too far, this is not within your legitimate function,’” Dershowitz told Hannity. “So, if I were one of the people who got a letter or a subpoena, I would at least think about the possibility of bringing a lawsuit and suggesting that Congress is abusing its oversight function.”