The kinetic energy release distribution (KERD) in the unimolecular H2 elimination reaction of the benzene molecular ion, which proceeds with a significant reverse critical energy, has been obtained. The existing statistical theories have been found inadequate to explain the experimental data. A modified statistical model which is an extension of a Marcus model has been proposed and the calculated result has been in fair agreement with the experimental data. The reason for some deviations from experimental KERD in both high and low kinetic energy release has been discussed.