  The initial $P$-invariance of the electroweak interaction Lagrangian together
with the low-energy results of the Weinberg-Salam model is provided by a local
secondary symmetry. Among the transformation parameters of this symmetry there
are both scalars, and pseudo-scalars with respect to the orthochronous Lorentz
group. Such symmetry does admissible existence of a light (massless) axial
gauge boson and its possible nonuniversal interaction with the leptons of
various types.
