War on terrorism will compel revisions to Posse Comitatus.

• Author: Kayyem, Juliette N.
• Position: Viewpoint

The war on terrorism has made the U.S. armed forces active participants in homeland defense and, in the process, has prompted changes in the responsibilities and mission scope of the Defense Department.

The most transparent of these changes has been the establishment of the U.S. Northern Command (NORTHCOM), a new unified combatant command that became operational on October 1.

NORTHCOM covers the geographic scope of the United States, Canada, Mexico, portions of the Caribbean and the U.S. coastal waters out to 500 nautical miles. Its stated goal is to provide support to civilian authorities in the event of a catastrophe and to deter, prevent and defeat any external threats against the United States.

In the process of standing up NORTHCOM, the Defense Department has had to address several operational issues involved with coordinating a new unified combatant command within the United States. How NORTHCOM will work with local and stare first responders in the event of a domestic terrorist attack is perhaps chief among them.

The Department of Defense, now consumed by a potential war with Iraq and its commitments around the globe, has provided many details in this regard. However, the question of the scope of the military's legal authority when acting within the United States raises significant concerns. The concept of an active standing army, whatever its contours, is unique--both as a matter of practice and law--in American history:

Posse Comitatus means "power of the county: Its origins can be traced to the election of 1876, when U.S. troops were ordered to police polling places in the South during Reconstruction.

Determined to prevent a recurrence, Congress passed the Posse Comitatus Act in 1878. It restricts the armed forces from acting "as a posse comitatus or otherwise to execute the laws," except "in cases and under circumstances expressly authorized by the Constitution or Act of Congress."

Lawmakers considered the act a success on two fronts: removing military enforcement of civilian law--precisely at times when it may be most threatened--helps guarantee individual rights and liberties while quelling long-standing citizen fears of standing armies.

This is not to suggest that the act is absolute. Constitutional authority gives the president and Congress the right to suspend Posse Comitatus during emergencies. Similarly, statutory exemptions, such as those encompassed by the Stafford Act 42 U.S.C [section]5122 and the Insurrection Act 10...