  Recently, it was demonstrated by Son et al., Phys. Rev. Lett. \textbf{102},
110404 (2009), that a separable bipartite continuous variable quantum system
can violate the Clauser-Horne-Shimony-Holt (CHSH) inequality via operationally
local transformations. Operationally local transformations are parameterized
only by local variables, however in order to allow violation of the CHSH
inequality a maximally entangled ancilla was necessary. The use of the
entangled ancilla in this scheme caused the state under test to become
dependent on the measurement choice one uses to calculate the CHSH inequality
thus violating one of the assumptions used in deriving a Bell inequality,
namely the `free will' or `statistical independence' assumption. The novelty in
this scheme however is that the measurement settings can be external free
parameters. In this paper we generalize these operationally local
transformations for multipartite Bell inequalities (with dichotomic
observables) and provide necessary and sufficient conditions for violation
within this scheme. Namely, a violation of a multipartite Bell inequality in
this setting is contingent on whether an ancillary system admits any realistic,
local hidden variable model i.e. whether the ancilla violates the given Bell
inequality. These results indicate that violation of a Bell inequality
performed on a system does not necessarily imply that the system is nonlocal.
In fact the system under test may be completely classical. However, nonlocality
must have resided somewhere, this may have been in the environment, the
physical variables used to manipulate the system or the detectors themselves
provided the measurement settings are external free variables.
