Transcript for Senator Lindsey Graham says the Senate will investigate Andrew McCabe's claim

To politics tonight, and the major headline involving Andrew Mccabe. Lindsey graham says the senate will investigate Mccabe's claim that he and rod Rosenstein discussed using the 25th amendment to remove president trump from office. Mccabe, who was fired one day before his retirement, says his words are being taken out of context. Graham calling the comments beyond stunning. Here's Tara Palmeri. Reporter: Tonight, a stunning admission from the former acting FBI director. Andrew Mccabe claiming that he and deputy attorney general rod rose had discussions about whether president trump was fit to serve and should be removed from office. The discussion of the 25th amendment was simply, rod raised the issue and discussed it with me in the context of thinking about how many other cabinet officials might support such an effort. Rosenstein was actually openly talking about whether there was a majority of the cabinet who would vote to remove the president? That's correct, counting votes or possible votes. Reporter: In an interview with "60 minutes," Mccabe saying the secret conversation took place in 2017, in the days after FBI director James Comey was fired. The deputy attorney general was definitely very concerned about the president, about his capacity, and about his intent. Reporter: Rosenstein denies discussing the president's removal. Mccabe is now downplaying his own words. His spokesperson saying he never had extended discussions but that he, quote, "Participated in a discussion that included a comment by Rosenstein regarding the 25th amendment." Mccabe was fired by president trump for leaking to the press. Trump saying Mccabe is a disgrace to the FBI and to the country. Tonight, Lindsey graham going so far as to call it an attempted takeover. The deputy attorney general was basically trying to do an administrative coup, take the president down through the 25th amendment process. The deputy attorney general denies it. Tara, joining us from Florida, where the president is spending the weekend. And Tara, Lindsey graham vowing to open an investigation into Mccabe's claim? Reporter: Tom, graham says plans to subpoena Mccabe and Rosenstein, unless they voluntarily agree to testify. Tom? Tara, thank Sticking with politics, president trump preparing to defend his declaration of a

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