High-resolution Auger electron spectra from the decay of the Cl 2p-->sigma* excitation in HCl and DCl have been measured. The spectra are analyzed, separating molecular and atomic features, which are assigned to transitions to the HCl (5 sigma 2 pi)(4) sigma* and Cl (3s3p)(6) states, respectively. Auger line shapes, as affected by the molecular dissociation, are studied by comparing the experiment with the results of Monte-Carlo computer simulations based on a semiclassical model.