MCALLEN – There are legal limitations to what the military can do when deployed to the U.S.-Mexico border.

The Posse Comitatus Act of 1878 limits the use of the military in the country. However, exemptions have been made to the rule.

“This is post-Civil War, and they’re worried about a president using the military to go and enforce state law within the South, former Confederate states,” explains South Texas College professor of political science, Mark Murray. “That’s why that was added, to prevent a president from abusing the military power – our Commander in Chief, to enforce domestic law.”

Watch the video above for more information.