Washington (CNN) – The U.S. government must keep all options open when it comes time to prosecute the perpetrator of Monday's bomb attacks in Boston, a Democratic lawmaker said Tuesday.
Sen. Carl Levin, D-Michigan, said the status of the individual or group of people responsible for the attack would dictate the manner of justice served.
"The option ought to be there for the Justice Department to prosecute the person as a criminal, or if that person has joined a foreign army, for that person to be held as an enemy combatant," Levin, who chairs the Senate Armed Services Committee, told reporters at the U.S. Capitol.
"It's important that the Justice Department has all the options of prosecution open to them. I don't want to foreclose any options, including prosecuting the person as a criminal, or if he's joined a foreign army, holding them as an enemy combatant," Levin continued.
The attacks in Boston, which came at the finish line of the city's annual marathon, are being investigated as an "act of terror," President Barack Obama said Tuesday. They left three people dead and scores injured.
Trying accused terrorists in civilian courts has been a political ordeal in the past, most recently in the case of Khalid Sheikh Mohammed, who is charged with masterminding the September 11, 2011 attacks.
The military initially charged Mohammed in 2008, but Obama stopped the case as part of his effort to close the U.S. detention center at Guantanamo Bay. As those efforts stalled, Obama attempted to move the case to federal court in New York in 2009, only to run into a political firestorm. The plan was dropped after complaints about cost and security.
Last April, Attorney General Eric Holder announced Mohammed, along with four other accused co-conspirators, would face a military trial at Guantanamo Bay.
Opponents of military tribunals argue they're a lower tier of justice, and the outcomes aren't regarded around the world as legitimate.
Since 9/11, high-profile terrorism cases have been convened in American civilian courts. The "underwear bomber," Umar Farouk Abdulmutallab, was tried and convicted of attempting to blow up an airliner in federal district court in Detroit.
Faisal Shahzad was convicted in a U.S. district court for the botched Times Square car bombing. And Richard Reid was convicted in district court of attempting to detonate explosives hidden in his sneakers on an American Airlines flight from Paris to Miami.
José Padilla, an American citizen, was originally arrested in 2002, accused of planning to set off radioactive "dirty bombs" in the United States. The military held the Chicago native for 3½ years as an enemy combatant without formally charging him in the alleged plot. Later, the government transferred him to civilian custody and brought criminal charges against him.