  We study the resonant tunneling effect in a many-body Wannier-Stark system,
realized by ultracold bosonic atoms in an optical lattice subjected to an
external Stark force. The properties of the many-body system are effectively
described in terms of upper-band excitation manifolds, which allow for the
study of the transition between regular and quantum chaotic spectral
statistics. We show that our system makes it possible to control the spectral
statistics locally in energy space by the competition of the force and the
interparticle interaction. By a time-dependent sweep of the Stark force the
dynamics is reduced to a Landau-Zener problem in the single-particle setting.
