  Extreme-Mass-Ratio Inspirals (EMRIs) are one of the most promising sources of
gravitational waves (GWs) for space-based detectors like the Laser
Interferometer Space Antenna (LISA). EMRIs consist of a compact stellar object
orbiting around a massive black hole (MBH). Since EMRI signals are expected to
be long lasting (containing of the order of hundred thousand cycles), they will
encode the structure of the MBH gravitational potential in a precise way such
that features depending on the theory of gravity governing the system may be
distinguished. That is, EMRI signals may be used to test gravity and the
geometry of black holes. However, the development of a practical methodology
for computing the generation and propagation of GWs from EMRIs in theories of
gravity different than General Relativity (GR) has only recently begun. In this
paper, we present a parameter estimation study of EMRIs in a particular
modification of GR, which is described by a four-dimensional Chern-Simons (CS)
gravitational term. We focus on determining to what extent a space-based GW
observatory like LISA could distinguish between GR and CS gravity through the
detection of GWs from EMRIs.
