In some switching circuits, peak currents/voltages (Dirac impulses) occur by changing the status of switches. These peak values are generally uncontinuous and uncontrolled variations. Because they include increases that change fast and have high magnitude, they may be dangerous for the system. These states which are uncountered very much in a linear and unswitched circuits must be examined before analysing of the system. If we assume that the switching occurs at t=0, the circuit which is normal before switching (t < 0(-)) may be uncontrolled and unstable after switching (t > 0(+)). In this paper, it's examined the reasons of uncontrolled states and it's shown how to apply controllability criteria to switching circuits. Moreover, it's also included an example of switching circuits.