The federal investigation into whether members of the Trump campaign colluded with Russian officials to subvert the 2016 election has legal experts debating if it is possible for a sitting president to be criminally prosecuted. If the probe concludes that President Donald Trump obstructed justice, it is unclear whether or not he could be indicted under the Constitution.
On May 17, Deputy Attorney General Rod Rosenstein appointed former FBI Director Robert Mueller as a special counsel to head the Department of Justice investigation into the Trump campaign's alleged ties to Russia. In response, Trump issued a statement asserting that the probe would not yield any incriminating evidence about his campaign, Reuters reports.
"As I have stated many times, a thorough investigation will confirm what we already know -- there was no collusion between my campaign and any foreign entity," Trump said.
Mueller's appointment came amid controversy surrounding Trump's dismissal of former FBI Director James Comey, who had been leading the federal probe of the Trump campaign.
On May 9, Trump fired Comey, saying that he no longer had confidence in the FBI director's ability to lead. It was later disclosed that Comey had penned a memo recounting a February meeting in which Trump allegedly asked Comey to drop a federal investigation into former White House National Security Adviser Michael Flynn, according to the Washington Post.
The Comey memo and ensuing Mueller appointment has drawn speculation that Trump could potentially be indicted for obstruction of justice. The Constitution did not address whether a sitting president could face criminal prosecution, according to The New York Times.
Article I of the Constitution states: "Judgment in cases of impeachment shall not extend further than to removal from office, and disqualification to hold and enjoy any office of honor, trust or profit under the United States: but the party convicted shall nevertheless be liable and subject to indictment, trial, judgment and punishment, according to law."
While the Constitution noted that president could face prosecution after being impeached from office, it did not outline whether a president could be criminally prosecuted without impeachment. The question was put to the Supreme Court during former President Richard Nixon's Watergate scandal, but the court never issued a ruling on the matter.
Professor Akhil Reed Amar of Yale asserted that the biggest takeaway from the Constitution is that a president cannot be indicted before impeachment.
"The framers implicitly immunized a sitting president from ordinary criminal prosecution," Amar said. The law professor added: "Donald Trump is to be judged by the House and the Senate, who are in turn judged on Election Day by the American people more generally."
Impeachment through the House and Senate has historically been the only legal method of removing a sitting president from office. On May 26, the nonpartisan Economist Intelligence Unit issued a skeptical assessment of the GOP-majority Congress taking such a dramatic step.
"We note that the president's impulsive character and disregard for protocol means that even the unlikely is possible," the EIU told Newsweek. "But it would take a significant shift in mood, even allowing for his existing transgressions, to shift Republican loyalty away from Trump."
Even if the federal investigation into the Trump campaign were to uncover incriminating evidence against the president, the probe could take Trump's full term or more. Historically, special investigations take an average of 3.5 years to run their full course, according to CBS News; one investigation in former Secretary of Housing and Urban Development Henry Cisneros took over 10 years.