Experimental findings have been interpreted by Copeland as indicating that the multiplication rate &agr;(E) of carriers in GaAs has a narrow peak between 3 and 10 kV/cm. It is argued here that theory can account for a sizeable &agr; at these low fields, but that, rather than having a maximum and decreasing to zero again, &agr; will continue to rise. The proposed variation of &agr; appears to be more consistent with experimental results.