It could be introduced in the UK to try and stop any riots that break out after we leave the EU on March 29.
But what is martial law and how does it work?
Martial law - officially called the Civil Contingencies Act - is the imposition of direct military control, to help deal with war, terrorism, or an emergency that threatens serious damage to human life or the environment.
Martial law gives authorities a range of powers - they could stop public rallies, impose curfews, limit movement and travel, and confiscate or destroy property.
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The law also allows government to change other laws to protect people or if they need to make sure we have access to money, food, water and fuel supplies.
The emergency regulations are usually only brought into force for a short period of time.
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