  One of the main purposes of long-baseline neutrino experiments is to
unambiguously measure the CP violating phase in the neutrino sector within the
three neutrino oscillation picture. In the presence of physics beyond the
Standard Model, the determination of the CP phase will be more difficult, due
to the already known degeneracy problem. Working in the framework of
non-standard interactions (NSI), we compute the appearance probabilities in an
exact analytical formulation and analyze the region of parameters where the
confusion problem is present. We also discuss some cases where the
falsification of the NSI parameters can be done in long-baseline experiments.
