Bracing for the possibility of “expanded unrest” in the embattled town of Ferguson, Missouri, Gov. Jay Nixon signed an executive order Monday activating the National Guard and declaring a state of emergency. The order comes as the nation awaits a grand jury decision regarding the investigation into the Aug. 9 shooting death of unarmed teenager Michael Brown.

The jury of 12 local residents is expected to issue a decision soon. Should the jury decide a crime was committed when Ferguson Police Officer Darren Wilson shot and killed the unarmed Brown, Wilson could be charged with murder. With tensions running high on both sides, Ferguson authorities are likely to have their hands full, regardless of the outcome.

In a statement, Nixon said the National Guard will support local law enforcement in the event of any “period of unrest” that might erupt in the wake of the grand jury’s decision. He said the order is part of the state’s efforts to be prepared for any possible contingency.

“The National Guard is well-suited to provide security at command posts, fire stations and other locations as well as perform other functions that will free up law enforcement officers to remain focused on community policing and protecting constitutional rights,” Nixon said.

Nixon’s order also requires three law enforcement departments -- the Highway Patrol, the St. Louis County Police Department and St. Louis Metropolitan Police Department -- operate under a unified command. The governor said officials will work to maintain public safety while protecting citizens’ right to exercise freedom of speech.

Law enforcement has been intensely criticized for its handling of the protests -- including firing tear gas at demonstrators and willfully suppressing journalists -- in the mostly black St. Louis suburb. Images of the harsh crowd-control methods sparked a nationwide conversation about a decades-long trend toward the militarization of America’s local police forces.  

Nixon said that under the executive order the St. Louis County Police Department will have “command and operational control over security in the city of Ferguson in areas of protests and acts of civil disobedience, should such activities occur.”

Read the full executive order here.

Christopher Zara is a senior writer who covers media and culture. Got a news tip? Email me  here. Follow me on Twitter @christopherzara.