Lindsey Graham: Trump-Russia investigation has evolved into a 'criminal investigation'

Sen. Lindsey Graham (R-SC) said after a closed-door Senate meeting on Thursday that the federal investigation into alleged collusion between the Trump campaign and Russian operatives now appears to be a criminal investigation.

"It was a counterintelligence investigation before now. It seems to me now to be considered a criminal investigation," he said after a meeting with Deputy Attorney General Rod Rosenstein.

"What does that mean for the Congress? I find it hard to subpoena records of somebody like Flynn who may be subject to a criminal investigation because he has a right not to incriminate himself," Graham added. "As to Comey, the former director of the FBI coming before the committee, if I were Mueller I would jealously guard the witness pool."

Rosenstein gave the impression that recently-appointed special counsel Robert Mueller was treating the investigation as a criminal matter, Graham explained.

Graham also said Trump should honor the Justice Department's decision to appoint a special counsel to oversee the investigation.

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