President Donald Trump tweeted last week that he might "send in the Feds" to help Chicago quell escalating violence. He didn't elaborate, leaving observers to guess at his intentions.
White House spokesman Sean Spicer didn't respond directly when asked whether Trump was talking about deploying National Guard troops to Chicago.
"There's no one thing," he said. "There can be aid, if it was requested up through the governor through the proper channels that the federal government can provide on a law enforcement basis. But there's other aid that can be extended as well through the U.S. attorney's office or other means that will ensure the people of Chicago have the resources to feel safe."
Typically, governors activate National Guard troops to assist local authorities with natural disasters or civil emergencies. That's what happened when rioting gripped Baltimore in 2015 after Freddie Gray's death. Gov. Larry Hogan sent in thousands of armed Maryland National Guard troops on armored Humvees to support Baltimore police as they restored order.
Presidents typically send the National Guard overseas, to participate in military action — as in the many deployments that the Maryland Guard has made to Afghanistan and Iraq over the last decade and a half.
Still, a president does have the authority to deploy troops domestically without gubernatorial support by invoking the Insurrection Act of 1807.
Presidents Dwight D. Eisenhower and John F. Kennedy used the legislation to send troops to Arkansas, Alabama and Mississippi to help desegregate schools and protect civil rights activists.
The Chicago Police Department already cooperates extensively with the FBI, DEA, the Department of Homeland Security and the Bureau of Alcohol, Tobacco, Firearms and Explosives.
Kanisha D. Bond, a professor of government and politics at the University of Maryland, said Trump's suggestion in the tweet is ironic.
"My guess is he's just flexing his new federal authority," she said. "Which is funny since he answered so many policy questions with 'let's leave it up to the states' during his campaign."