  We analyze, in the context of a simple toy model, for which renormalization
schemes the CP-properties of bare Lagrangian and its finite part coincide. We
show that this is the case for the minimal subtraction and on-shell schemes.
The CP-properties of the theory can then be characterized by CP-odd basis
invariants expressed in terms of renormalized masses and couplings. For the
minimal subtraction scheme we furthermore show that in CP-conserving theories
the CP-odd basis invariants are zero at any scale but are not renormalization
group invariant in CP-violating ones.
