  We present an electronic transport experiment in graphene where both
classical and quantum mechanical charge detector back-action on a quantum dot
are investigated. The device consists of two stacked graphene quantum dots
separated by a thin layer of boron nitride. This device is fabricated by van
der Waals stacking and is equipped with separate source and drain contacts to
both dots. By applying a finite bias to one quantum dot, a current is induced
in the other unbiased dot. We present an explanation of the observed
measurement-induced current based on strong capacitive coupling and energy
dependent tunneling barriers, breaking the spatial symmetry in the unbiased
system. This is a special feature of graphene-based quantum devices. The
experimental observation of transport in classically forbidden regimes is
understood by considering higher order quantum mechanical back-action
mechanisms.
