[en] Protoionization and photodetachment of atoms in a homogeneous electric field are considered whithout taking into account the interaction between the electron and atomic residue in the final state. Expressions for the total cross sections of the processes and for the angular electron distribution are derived in the quasiclassical and semiclassical approximations. It is shown that the oscillating dependence of the cross sections on the energy is due to interference of the classical trajectories of an electron moving in a homogeneous electric field