In 1986, Maine Gov. Joseph Brennan refused to send 48 members of the Maine National Guard to a training exercise in Honduras.

According to a 1991 article in the Colorado Law Review, Brennan was concerned that the road-building exercise in Central America, which was torn by civil unrest, would put the guard members in danger.

Instead of building roads in Honduras, Brennan ordered that the guard work on 40 road projects in Maine.

The governor of Ohio declined a similar request to deploy, and several other governors said they would not send their guard to Central America if asked.

In 1985, President Ronald Reagan had determined that the leftist government of Nicaragua was an “unusual and extraordinary threat to the national security” and declared a national emergency to deal with the situation.

At the time, federal law required governors to consent to federal activation unless the activation occurred during a time of war or national emergency.

After the confrontation in 1986, the Pentagon asked Congress to clarify the relationship between federal and state governments in regards to deploying the National Guard.

An amendment was added to the National Defense Authorization Act of 1987 that stripped governors of their ability to block overseas deployment of National Guard soldiers. The law was appealed, but ultimately upheld by the Supreme Court.

The court ruled in Perpich v. Department of Defense that Congress can “authorize the president to order members of the National Guard to active duty for purposes of training outside the United States during peace time without either the consent of a state governor or the declaration of a national emergency.”

Source: University of Colorado Law Review, 1991, “Perpich v. Department of Defense: Federalism Values and the Militia Clause.”