Abstract: A holder for attaching a firearm, such as a Taser™ gun, to a Remote Mobile Investigator (RMI) robot equipped with a firing interface is disclosed. The holder comprises a housing portion defining a cavity portion for receiving the firearm, the housing portion having a first opening aligned with the barrel of the firearm, thereby allowing the firearm to be fired when housed in the holder and attached to the robot. The housing portion also includes a second opening for establishing an operable connection between the firearm and the firing interface of the robot. A plate member is hingedly attached to the housing portion, the plate member having an open position providing access to the cavity portion, and a closed position sealing the cavity portion. First and second locking devices are provided for releaseably securing the plate member in the closed position and for locking the holder on to the robot.