  We explore the possibility to break time reversal invariance at the junction
of quantum wires. The universal features in the bulk of the wires are described
by the anyon Luttinger liquid. A simple necessary and sufficient condition for
the breaking of time reversal invariance is formulated in terms of the
scattering matrix at the junction. The phase diagram of a junction with generic
number of wires is investigated in this framework. We give an explicit
classification of those critical points which can be reached by bosonization
and study the interplay between their stability and symmetry content.
