  We analyze possible CP-violating effects induced in the $Z$ decay with hard
photon radiation by $\gamma ZZ$ and $\gamma\gamma Z$ anomalous vertices. We
estimate the sensibility of future linear collider experiments on these
couplings coming from CP-odd asymmetries associated to angular correlations of
the three particle final state in $e^+e^- \to Z \to \mu^+\mu^-\gamma$. We find
that a linear collider with an integrated luminosity of 500 $fb^{-1}$ and
$\sqrt{s} = 0.05$ TeV can place the bound $|h_1^{\gamma,Z}| < 0.92$ at the 90%
confidence level for these couplings.
