The Posse Comitatus Act of 1878 bars the military from making arrests, conducting searches or engaging in other police activity on US soil. Only the Coast Guard and the National Guard are exempt from the law.

The origin of The Posse Comitatus Act was the Civil War, during which civilians were tried and sometimes executed by military courts. US troops occupied the defeated southern states for several years after the war.

In 1981, Congress modified the act by authroizing the use of military troops and equipment to prevent the importation of illegal drugs.

Now President Bush, Homeland Security Chief Tom Ridge and Senator Joseph Biden (D-Del) are discussing changes to the law to allow the military a greater role in law enforcement when it comes to fighting terrorism.

We don't think the law should be weakened any further. For some reasons why, check out "The Posse Comitatus Act: A Principle in Need of Renewal "(Washington Universitys Law Quarterly)