"I'm here to defend the Constitution, not any particular president," he said. "I'm here to defend future presidents, as well as the current president."
His arguments against impeachment have largely been constitutional during the Senate trial, centered on the idea that the two articles of impeachment brought forth by the House against Trump -- "abuse of power" and "obstruction of Congress" -- are not impeachable offenses.
Dershowitz, a celebrity lawyer and Harvard emeritus, told the hosts he would have made the same argument regardless of the president on trial.
"I would have been making exactly the same argument if Hillary Clinton was elected president and if she had been impeached for abuse of power or obstruction of Congress," he said, adding "the framers rejected terms just like that. They rejected maladministration as a potential term. And maladministration is virtually the same as abuse of power."
The New York Times article in a way changed the conversation on whether witnesses should be allowed on the Senate floor during the impeachment trial -- and what Bolton, if subpoenaed, would say has been the source of much speculation.
When asked about the news, Dershowitz told "The View" hosts that he won't argue against witnesses, but said Bolton's testimony still wouldn't hold up against the president.
"Nothing in the Bolton revelations, even if true, would rise to the level of an abuse of power or an impeachable offense." he said, adding that House Democrats can't change that just by using words like "quid pro quo" and "personal benefit."
Bolton and other current and former White House aides have been barred by the White House from testifying, although Bolton said he would testify under subpoena.
"The one thing that's very clear is that if witnesses are permitted on one side, they have to be permitted on both sides," Dershowitz said in an interview on "This Week with George Stephanopoulos" on Jan. 19. "And if witnesses are permitted, it will delay the trial considerably, because the president will invoke executive privilege as to people like John Bolton that will have to go to the court and we'll have to have a resolution of that before the trial continues."
Talking over each other and Dershowitz, the hosts also pressed the lawyer on why he seems to be the only constitutional scholar arguing that Trump's conduct wasn't impeachable.
"I made the constitutional arguments. My sole role in the case was to argue constitutional issues," he said, later adding, "It is not treason, bribery [or] high crimes and misdemeanors ... Congress is not above the law."
He further argued the point he made during the Trump legal team's opening arguments on the Senate floor, saying the articles brought forth by the House trial managers were too "vague" and "open-ended."
"This is the key point in this impeachment case, please understand what I'm arguing, is that purely noncriminal conduct, including abuse of power and obstruction of Congress are outside the range of impeachable offenses," Dershowitz said on the floor Monday evening, adding "The framers did intend to limit the criteria for impeachment to criminal-like conduct akin to treason and bribery."
Dershowitz has not said the president's conduct in Ukraine was right or wrong -- but did say it hasn't been declared criminal.
Despite the Government Accountability Office report on Jan. 16 concluding that Trump did violate the law by withholding the aid, Dershowitz argued that Congress doesn't have the "jurisdiction to conclude it’s a crime."
"The president conducts foreign policy," Dershowitz said. " He has the right to withhold funds."
"It certainly doesn’t have to be a crime," Dershowitz said in a 1998 interview on CNN of the trial. "If you have somebody who completely corrupts the office of president, who abuses trust and who poses great danger to our liberty, you don’t need a technical crime."
Host Whoopi Goldberg brought up what he said during the interview, pointing out what she called the "only difference" between the two trials.
"The only difference between then and now is that your side was flipping out for the same reasons the democrats were flipping out," she said. "The difference is one president followed the law and sat down and did what he was supposed to do."
Dershowitz said the issue during Clinton's trial was not whether or not you needed a crime to impeach a president, but "whether or not Clinton had committed a high crime."
Goldberg continued to question his wavering opinion, saying, "I have not seen any briefs about your change of heart when it comes to impeachment."
"Academics change their minds on the basis of research," Dershowitz responded without flinching. "I didn’t do it on a partisan basis."
Host Meghan McCain also questioned the lawyer about his connection as a lawyer to convicted sex offender Jeffrey Epstein, who committed suicide in his cell in August.
Dershowitz said he was candid about their connection when Trump expressed interest in bringing him on as a defense lawyer.
"I told him this [connection] would be raised, and he should seriously consider if he wants me as his lawyer," Dershowitz said.
The announcement of Dershowitz joining Trump’s legal team came as a surprise to some.
However, Trump told his associates he wanted a "high profile" legal team that could perform on TV, explaining why Dershowitz and former independent counsel Kenneth Starr both ended up on the team.
Although critics argue Dershowitz statements from the past contradict his stance on impeachment now, Dershowitz continued to defend himself in a previous statement to ABC News.
"That’s still my position. It has to be criminal -- like, akin to treason or bribery," he said of impeachment. "Not abuse or obstruction."
ABC News' John Santucci, Benjamin Siegel, Katherine Faulders and Adia Robinson contributed to this report.