  We have studied the chiral phase transition in three-dimensional QED in the
presence of a Chern--Simons term for the gauge field. There exists a phase
where the chiral symmetry is broken dynamically and we have determined the
critical line for this symmetry breaking as a function of the effective
coupling and the strength of the additional Chern--Simons term. In the presence
of a Chern--Simons term, the chiral phase transition turns out to be first
order, in sharp contrast to the phase transition in pure three-dimensional QED.
