Bands of the CO(A1&Pgr;-X1&Sgr;+) fourth-positive group (4PG) were excited by electron impact dissociative excitation of CO2, and their rotational profiles were measured. The corresponding rotational distributions were found to be nonthermal but rotationally 'hot' with respect to a 300¿K distribution. Bands originating from &ngr;'=0 have 1 have similar rotational distributions, which are 'hotter' than the distribution for &ngr;'=2. The rotational profiels were measured at selected electron impact energies in the range from 20 to 300 eV. The rotational distributions for all three levels become broader with increasing electron energy and 'saturate' at about 40 eV. This may mean that dissociation through bent states becomes relatively more important as the dipole-allowed limit is reached, whereas linear states are relatively more important at very low electron energies. The low-energy profiles for &ngr;'=0 and 1 are reproduced by a model that assumes that the CO fragment carries away all of the rotational angular momentum of the CO2 parent, but this model fails for &ngr;'=2. The results are discussed in terms of their applicability to the Mariner observations of the CO 4PG in the dayglow of Mars.