A system for the emergency deenergization of a multibranch power circuit includes a ground fault circuit interrupter having capability to trip under both ground fault and grounded neutral conditions. A plurality of receptacles are provided on the circuit to receive connecting plugs of electrical devices to be powered. A removable plug adapted for insertion into any of the receptacles includes the series combination of a normally open pushbutton switch and resistor connected between plug pins which are in contact with the neutral and ground conductors of the circuit so that actuation of the switch when the plug is inserted in a receptacle establishes a low-impedance path from neutral to ground which is detected by the ground fault circuit interrupter. This causes the interrupter to trip and deenergize the circuit.