  We introduce a rate formalism to treat classically forbidden electron
transport through a quantum dot (cotunneling) in the presence of a coupled
measurement device. We demonstrate this formalism for a toy model case of
cotunneling through a single-level dot while being coupled to a strongly
pinched-off quantum point contact (QPC). We find that the detector generates
three types of back-action: the measurement collapses the coherent transport
through the virtual state, but at the same time allows for QPC-assisted
incoherent transport, and widens the dot level. Last, we obtain the measured
cotunneling time from the cross correlation between dot and QPC currents.
