A surgical instrument is disclosed. The instrument includes an end effector comprising a moveable cutting instrument to cut an object and a motor coupled to the end effector. The motor actuates the cutting instrument in response to a current therethrough, causing the cutting instrument to move between a proximal-most position and a distal-most position. The instrument includes an interlock coupled to the end effector and to the motor to prevent actuation of the cutting instrument based on the current through the motor.