The case, filed by Public Citizen in federal district court in Washington, DC, is the first of what are expected to be multiple lawsuits challenging Trump’s unprecedented decision to declare a national emergency in order to access $3.6 billion in military construction funds to pay for more sections of the wall he promised to build along the US–Mexico border…

Public Citizen is arguing the president exceeded his authority under the federal National Emergencies Act because there is no emergency at the southern border, and that his declaration of a national emergency in order to build the wall violates the separation of powers — essentially, that it’s unconstitutional for Trump to declare an emergency because Congress already refused to appropriate the money.