  The critical behaviour of three-dimensional disordered systems is
investigated by analysing the spectral fluctuations of the energy spectrum. Our
results suggest that the initial symmetries (orthogonal, unitary and
symplectic) are broken by the disorder at the critical point. The critical
behaviour, determinedby the symmetry at the critical point, should therefore be
independent of the previous invariances and be described by a ``super''
universality class. This result is strongly supported by the fact that we
obtain the same critical exponent $\nu \simeq 1.35$ in the three cases:
orthogonal, unitary and symplectic.
